Beat Work Index, Cardiac Power Index, and Arterial Elastance Index: a novel non-invasive approach to assessing hemodynamic status in children following cardiovascular surgery

Introduction

Accurate and timely hemodynamic assessment is fundamental to the management of critically ill children, particularly following cardiovascular surgery. Postoperative low cardiac output syndrome and pediatric cardiogenic shock remain major contributors to morbidity and mortality, yet early recognition continues to rely on surrogate and operator-dependent parameters. Despite significant progress in pediatric intensive care, optimal assessment of circulatory physiology remains challenging, as conventional measures provide a limited description of cardiovascular performance (1,2).

Traditional bedside evaluation—heart rate (HR), arterial pressure, capillary refill, and urine output—can suggest perfusion abnormalities but lacks specificity, as these signs are influenced by non-hemodynamic factors such as temperature, emotional stress, or fever (3,4). Echocardiography remains the cornerstone of non-invasive cardiac monitoring, but it too has important limitations. The accuracy of volumetric and geometric assumptions varies among techniques, and image-quality dependence restricts reproducibility, particularly in critically ill children (5).

Standard echocardiographic metrics such as left ventricular ejection fraction (LVEF) and cardiac output quantify stroke volume (SV) and global systolic shortening but do not capture the energetic capacity of the heart to sustain systemic flow (6). Furthermore, compensatory mechanisms—tachycardia, increased contractility, or afterload adjustments—can maintain a normal LVEF despite significant reductions in effective forward energy, masking early circulatory compromise.

Cardiac power output (CPO), calculated as the product of cardiac output and mean arterial pressure (MAP), represents the rate of hydraulic energy transferred to the arterial system and is one of the strongest invasive predictors of outcomes in adult cardiogenic shock and heart failure (7,8). However, CPO expresses energy delivered per second and does not reflect the energetic strength of each individual contraction, which may differ markedly between tachycardic and bradycardic states with similar average power.

To address this gap, the present proof-of-concept study introduces a non-invasive energetic framework based on standard Doppler echocardiography and arterial-pressure measurements. This approach quantifies the hydraulic energy transferred per beat and its temporal integration as energy per second, together with the arterial impedance opposing that transfer, thereby describing both sides of ventricular-arterial interaction. Three indices are proposed:

• Beat Work Index (BWI): the hydraulic energy transferred with each contraction (joules per beat);
• Cardiac Power Index (CPI): the temporal integration of BWI, expressing energy transferred per second (watts).
• Arterial Elastance Index (AEI): a non-invasive measure of vascular impedance and ventricular-arterial coupling (mmHg/mL).

Collectively, these indices provide a physiologically grounded, quantitative framework to evaluate cardiac energy generation, vascular load, and their interaction in real time.

The aim of this study was to explore the feasibility, physiologic coherence, and clinical relevance of these indices in healthy children and in those following congenital heart surgery. We hypothesized that BWI, CPI, and AEI would discriminate postoperative circulatory states more effectively than conventional echocardiographic metrics and correlate with clinically meaningful outcomes, thereby establishing the foundation for a new beat-level energetic paradigm in hemodynamic monitoring. We present this article in accordance with the STROBE reporting checklist (available at https://shc.amegroups.com/article/view/10.21037/shc-24-30/rc).

Methods

Design and participants

This was a retrospective case-control study conducted in a pediatric population (<18 years). Cases were defined as postoperative children (<18 years old) in critical care unit following cardiovascular surgery for the correction of congenital heart disease with biventricular circulation, and in whom no intervention was performed at the level of the left ventricular outflow tract and/or the aortic valve, and with no residual or intentional shunts. Controls were healthy children (without structural or functional heart disease) who underwent outpatient transthoracic echocardiography for an evaluation of a heart murmur suspected at our echocardiography lab. Cases were identified using non-random purposive sampling, including all patients who met the inclusion criteria between January 1^st and August 1^st, 2025, and for each case, one control was randomly selected, matched by sex, age, and weight.

Echocardiographic protocol

All transthoracic echocardiogram examinations were performed by two certified pediatric sonographers using either an Affiniti 70 (probes 68-3/X5-1, Philips, Best, The Netherlands) or Vivid S70 N (probes M5Sc–6s, GE Healthcare, Chicago, IL, USA). Both operators had advanced training in congenital heart disease, and all studies were reviewed by the laboratory’s chief pediatric cardiologist. Measurements followed the Guidelines and Standards for Performance of a Pediatric Echocardiogram of the American Society of Echocardiography (9). The left ventricular outflow tract velocity-time integral (LVOT VTI), LVEF (Simpson method), HR, and non-invasive arterial pressures were obtained for each subject. LVOT VTI was selected as the principal flow variable because it directly represents blood displacement per beat through the LVOT, allowing assessment of stroke work when combined with MAP.

Definition and calculation of energetic indices

The proposed energetic framework quantifies the hydraulic energy transferred by the ventricle to the arterial system with each heartbeat and the vascular impedance that modulates this transfer (Figure 1A). All calculations derive from Doppler-measured LVOT VTI and non-invasive MAP.

Figure 1 Conceptual representation of energetic indices. (A) Stroke work in a PV loop. Hydraulic work per beat corresponds to the area within the PV loop, representing the energy generated by the left ventricle to eject one stroke volume. (B) Non-invasive Beat Work Index. The product of MAP and indexed stroke volume (VTI × LVOT area) yields the beat-level energy transfer expressed in joules per beat. (C) Echocardiographic derivation of indexed stroke volume. The LVOT diameter and Doppler VTI are used to calculate stroke volume and its indexed form for BWI estimation. (D) Arterial elastance in a PV loop. The slope connecting the end-systolic point and the volume axis reflects the relationship between pressure and volume at the end of ejection, representing total arterial load. (E) Non-invasive Indexed Arterial Elastance. The ratio of MAP to indexed stroke volume defines vascular impedance, complementing BWI in the evaluation of ventriculo-arterial coupling. BWI, Beat Work Index; LA, left atrial; LV, left ventricular; LVOT, left ventricular outflow tract; MAP, mean arterial pressure; PV, pressure volume; VTI, velocity-time integral.

BWI

BWI expresses the hydraulic work performed by the ventricle per beat, in joules (J) (Figure 1B). To maintain dimensional coherence, an SV rather than a raw VTI was required. Direct LVOT area measurement introduces variability because it depends on the squared diameter and changes with growth. Therefore, a standardized LVOT diameter of 2 cm (area =3.1416 cm²) was adopted as a fixed geometric scaling factor (Figure 1C). This standardization indexes the measured VTI to a reference LVOT, avoids squared-error propagation, and enables conversion of pressure-displacement products into energy units.

BWI(J)=LVOTVTI(cm)×MAP(mmHg)×0.00041881[1]

where k=0.00041884 incorporates the standardized LVOT area and converts pressure (mmHg) × distance (cm) into joules.

CPI

CPI represents the temporal integration of BWI, expressing the rate of energy transfer per second, in watts (W):

CPI(W)=BWI×HR60sec⁡[2]

Thus, BWI quantifies energy per beat, while CPI quantifies energy per second, analogous to mechanical power output.

AEI

AEI characterizes the arterial impedance opposing ventricular ejection, serving as a non-invasive surrogate of afterload and ventricular-arterial coupling (Figure 1D).

AEI(mmHg/mL)=MAPIndexedStrokeVolume[3]

where the Indexed Stroke Volume = VTI × 3.1416 cm² (standardized LVOT area). AEI represents the pressure required to eject each milliliter of blood and provides a practical measure of arterial stiffness and coupling efficiency (Figure 1E). A full dimensional derivation of the constant k, the geometric assumptions underlying the standardized LVOT, and example calculations are presented in Appendix 1.

Variables and clinical outcomes

For all patients, data on sex, age, body weight, systolic, diastolic, and MAPs, HR, LVEF, and velocity time integral (VTI) were collected. In postoperative patients, the vasoactive-inotropic score (VIS) (10) was assessed on postoperative days 1 and 5, and the intensive care unit (ICU) postoperative length of stay (PLOS) was defined as the number of days between surgery and ICU discharge. Adverse recovery pattern (ARP) was defined as the presence of a VIS ≥10 on postoperative day 1, a VIS >0 on day 5, and a PLOS exceeding 8 days. These thresholds were selected based on established literature demonstrating that early elevated VIS is strongly associated with postoperative morbidity and mortality (10,11), that persistent vasoactive requirements beyond postoperative day 3–5 reflect ongoing low-output physiology and impaired ventricular-arterial interaction (12), and that prolonged postoperative ICU length of stay (>7–10 days) is a widely used indicator of complicated recovery and major morbidity after congenital heart surgery (13). These clinically validated components were therefore integrated into a composite adverse recovery definition tailored for this proof-of-concept study

Statistical analysis

Qualitative variables were summarized as absolute and relative frequencies. Continuous variables were described using measures of central tendency and dispersion, according to their distribution. The normality of continuous variables was assessed through graphical methods and the Shapiro-Wilk test. Comparisons between groups were performed using the chi-squared test or Fisher’s exact test for qualitative variables, and the t-test or the Wilcoxon rank-sum test for quantitative variables, as appropriate. The correlations between echocardiographic parameters and LVEF, VIS and PLOS were assessed using Pearson’s correlation coefficient. A two-sided P value <0.05 was considered statistically significant. Two logistic regression models were constructed with ARP as the dependent variable. The first model included the BWI as predictor, and the second included LVEF. Model performance was evaluated through receiver operating characteristic (ROC) curve analysis to assess discriminative ability. The area under the curve (AUC) and its 95% confidence interval (CI) were calculated for each model, and the curves were compared using the DeLong test implemented through the roccomp command in Stata. The optimal cutoff for BWI was estimated from the ROC curve using the Youden index (J = sensitivity + specificity − 1), representing the point with the best trade-off between sensitivity and specificity.

The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. Ethical approval was obtained from the Ethics Committee of Fundación Cardiovascular de Colombia (No. CEI-2024-08218). As this analysis used anonymized data from an institutional database, the requirement for informed consent was waived by the committee.

Results

Population characteristics

A total of 92 children were included in the study, 46 postoperative patients following surgical correction of congenital heart disease and 46 healthy controls (Figure 2). The median age was 7 years [interquartile range (IQR): 0.8–12 years], and 52% were male, with no significant differences in age or sex distribution between groups. Postoperative patients exhibited a hyperadrenergic-low-pressure profile typical of early low-output physiology, characterized by a higher HR [median 111 (90–133) vs. 91 (78–114) beats/min; P=0.003] and lower diastolic (56.5±12.0 vs. 62.5±9.1 mmHg; P=0.009) and MAPs (70.1±12.0 vs. 74.5±8.3 mmHg; P=0.04). No differences were found in body weight or systolic pressure (Table 1).

Figure 2 Flowchart for patient selection. Index surgery: the primary cardiovascular procedure requiring cardiopulmonary bypass during the hospital admission. LVOT interventions: aortic stenosis subvalvular repair + aortic valvuloplasty (n=2), isolated aortic valvuloplasty (n=2), Konno procedure + aortic valve replacement (n=1), Rastelli procedure (n=1), aortic dissection repair + aortic valvuloplasty (n=1). LVOT, left ventricular outflow tract.

Postoperative children exhibited significantly lower LVEF compared to healthy controls [median 51.5% (IQR, 43–55%) vs. 62% (IQR, 59–67%); P<0.001]. Similarly, the VTI was reduced in the postoperative group (14.9±4.9 vs. 20.5±4.5 cm; P<0.001).

All three newly derived energetic indices showed significant and directionally coherent differences between groups. The BWI decreased by 31% (0.44±0.17 vs. 0.64±0.17 J; P<0.001) and the CPI fell by 19% (0.79±0.29 vs. 0.98±0.18 W; P<0.001) in postoperative patients compared to controls. Conversely, the AEI increased by 26% [1.47 (IQR, 1.20–1.94) vs. 1.16 (IQR, 0.99–1.39) mmHg/mL; P<0.001] (Table 1, Figure 3).

Figure 3 Distribution of indexed echocardiographic parameters by groups. AEI, Arterial Elastance Index; BWI, Beat Work Index; CPI, Cardiac Power Index.

Correlation analysis

Across the entire cohort, LVEF correlated positively with both BWI (r=0.36, 95% CI: 0.16–0.52, P<0.001, Figure 4A) and CPI (r=0.32, 95% CI: 0.12–0.49, P=0.002, Figure 4B) and inversely with AEI (r=−0.39, 95% CI: −0.55 to −0.20, P<0.001, Figure 4C), indicating that higher hemodynamic performance aligns with greater energetic output and lower afterload. Within postoperative patients, higher vasoactive-inotropic requirements were associated with energetic depression: VIS on day 1 correlated negatively with BWI (r=−0.55, 95% CI: −0.72 to −0.31, P<0.001, Figure 5A) and CPI (r=−0.45, 95% CI: −0.65 to −0.18, P=0.001, Figure 5B) and positively with AEI (r=0.38, 95% CI: 0.10–0.60, P=0.008). Longer PLOS was strongly associated with lower BWI and CPI (r=−0.65, P<0.001, r=−0.52, P<0.001, respectively). On the other hand, AEI showed a positive correlation with PLOS (r=0.42, P=0.002).

Figure 4 Relationship between LVEF and energetic indices (BWI, CPI, and AEI) by group. (A) Relationship between LVEF and BWI. (B) Relationship between LVEF and CPI. (C) Relationship between LVEF and AEI. AEI, Arterial Elastance Index; BWI, Beat Work Index; CPI, Cardiac Power Index; LVEF, left ventricular ejection fraction.

Figure 5 Relationship between postoperative VIS and PLOS with echocardiographic parameters (BWI, CPI, and AEI). (A) Correlation between VIS on postoperative day 1 and the energetic indices. (B) Correlation between PLOS and the energetic indices. AEI, Arterial Elastance Index; BWI, Beat Work Index; CPI, Cardiac Power Index; PLOS, postoperative length of stay; POP, postoperative; VIS, vasoactive-inotropic score.

ARP

Fifteen patients (32.6%) met predefined criteria for an ARP. These patients had higher VIS on both postoperative days 1 and 5, as well as a significantly longer postoperative ICU stay. Energetic indices exhibited the strongest contrasts (Table 2): BWI was 46% lower (0.28±0.10 vs. 0.52±0.10 J; P<0.001); CPI declined by 37% (0.57±0.10 vs. 0.90±0.20 W; P<0.001); AEI almost doubled [2.00 (IQR, 1.50–2.69) vs. 1.33 (IQR, 1.19–1.54) mmHg/mL; P<0.001]. Parallel reductions in LVEF (48.6%±10.9% vs. 62.8%±6.0%; P<0.001) corroborate the energetic deficit. These findings identify a distinct postoperative phenotype characterized by reduced per-beat energy transfer and excessive arterial load in children with delayed recovery.

In the plot of BWI vs. AEI, the two recovery groups showed clearly different distributions (Figure 6). Patients without an ARP were largely concentrated in the area of higher BWI and lower AEI, forming a dense cluster in the upper-left region of the graph. In contrast, patients with an ARP appeared predominantly in the lower-BWI/higher-AEI region, with fewer points overlapping the distribution of the no ARP group. The spatial separation between groups was visually evident, with ARP points occupying a wider range of AEI values and consistently lower BWI values across the scatter.

Figure 6 Relationship between beat work and arterial elastance according to recovery pattern. AEI, Arterial Elastance Index; ARP, adverse recovery pattern; BWI, Beat Work Index.

The ROC analysis demonstrated that the model based on BWI exhibited excellent discriminative ability for identifying patients with ARP, with an AUC of 0.87 (95% CI: 0.75–0.99). In contrast, the model based on LVEF showed only modest discrimination, with an AUC of 0.64 (95% CI: 0.47–0.81) (Figure 7). The DeLong test confirmed the superiority of the BWI model (P=0.01). The optimal threshold was determined using the Youden index, which identified an BWI cutoff value of approximately 0.32, corresponding to a sensitivity of 93% and a specificity of 67%.

Figure 7 ROC curves comparing the predictive performance of models based on BWI and LVEF for adverse recovery. BWI, Beat Work Index; CI, confidence interval; LVEF, left ventricular ejection fraction; ROC, receiver operating characteristic.

Discussion

This proof-of-concept study introduces and clinically evaluates three non-invasive energetic indices—BWI, CPI, and AEI—derived from standard Doppler echocardiography and non-invasive arterial-pressure measurements. These parameters quantify the hydraulic energy transferred from the left ventricle to the arterial system on a per-beat (BWI) and per-second (CPI) basis, while AEI reflects the vascular impedance and ventricular-arterial coupling that govern this transfer.

Non-invasive hemodynamic assessment in children remains technically demanding. Current methods for estimating cardiac output or circulatory efficiency—such as Doppler-derived stroke volume, impedance cardiography, or ultrasound dilution—require expertise and show variable accuracy and reproducibility in pediatrics (12,14). Consequently, reliable and practical markers of cardiovascular performance are still lacking.

Studies of ventricular-arterial coupling and arterial elastance have demonstrated physiologic and prognostic value after congenital heart surgery (15), yet their complexity limits routine clinical use. To date, the energy transferred between the ventricle and arterial system—a direct representation of circulatory performance—has never been quantified non-invasively in adults or children.

Within this context, the present study provides the first human demonstration that BWI, CPI, and AEI can be derived from routine echocardiographic and non-invasive arterial pressure data to characterize ventricular energy delivery and vascular load. Validated here in a postoperative pediatric cohort, these indices showed physiologic coherence and superior clinical discrimination compared with LVEF (12,14).

From concept to clinical signal

This energetic framework reframes hemodynamic evaluation from a volumetric to an energy-transfer perspective, emphasizing how the heart transmits hydraulic energy to sustain systemic flow. Conventional measures such as cardiac output or ejection fraction quantify blood volume ejected, but not the energy effectively delivered to the circulation. In pediatric patients, particularly after cardiopulmonary bypass, this limitation becomes evident: normal ejection fraction may coexist with inadequate systemic perfusion due to altered ventricular-arterial coupling and increased arterial elastance (12,16). By integrating the LVOT VTI, a robust Doppler measure of stroke displacement (17)—with arterial pressure, BWI and CPI quantify the hydraulic energy transferred per beat and per second, respectively. AEI, in turn, represents the vascular impedance opposing this transfer, serving as a non-invasive surrogate of ventricular-arterial coupling (15).

In this first clinical application, the pattern of reduced BWI and CPI with elevated AEI defined a low-energy-transfer, high-impedance state consistent with postoperative low-output physiology. The concordance of these indices with observed blood-pressure and heart-rate changes supports their physiologic validity and confirms that they capture fundamental dynamics of energy exchange between the ventricle and arterial system. The distinct distribution of BWI and AEI observed between groups suggests that children with an ARP operate in a hemodynamic configuration characterized by reduced beat-level energy transfer and elevated arterial load. This combination reflects an unfavourable ventricular-arterial coupling state, in which the ventricle generates less hydraulic work while simultaneously facing higher effective elastance from the arterial tree. In practical terms, each systolic ejection in ARP patients contributes less useful energy to the circulation and must do so against a stiffer vascular system. Such a configuration reduces the efficiency of cardiovascular energy transfer and increases the vulnerability of these patients to low-output physiology. The clustering of ARP patients in the low-BWI/high-AEI quadrant therefore, highlights a pattern of impaired energetic delivery that aligns with their greater postoperative support needs and delayed clinical stabilization.

Physiologic interpretation

Children with uncomplicated postoperative recovery maintained higher BWI and CPI values in immediate postoperative period, indicating efficient transfer of hydraulic energy from the left ventricle to the arterial system. Conversely, those who developed an ARP showed markedly lower energetic indices and elevated AEI—evidence of impaired energy transfer and increased left ventricular afterload. These differences were present even when LVEF remained within the conventional normal value, consistent with prior pediatric observations that volumetric indices may fail to reveal early hemodynamic compromise following cardiovascular surgery (18).

The inverse association between BWI/CPI and VIS indicates that diminishing energetic performance parallels greater inotropic therapy needs, in agreement with earlier pediatric studies linking VIS with postoperative morbidity and mortality (11). The direct correlation between AEI and postoperative ICU (PLOS) stay further underscores the role of vascular impedance in recovery, echoing reports that increased arterial elastance correlates with prolonged intensive-care courses in children (12).

Collectively, these relationships delineate a continuum of postoperative hemodynamics—from preserved energy transfer and optimal coupling to energetic failure and excessive impedance—providing an integrated view that bridges ventricular mechanics, vascular load, and clinical trajectory in the pediatric population.

Comparison with existing paradigms

CPO, obtained from the product of cardiac output and MAP, expresses the average hydraulic energy delivered per second and has long been recognized as a strong predictor of outcomes in cardiogenic shock and heart failure (7,8).

However, CPO reflects continuous power rather than the energetic strength of each individual heartbeat. Two patients can display identical cardiac power—one maintaining output through tachycardia and another through strong, efficient contractions—yet their per-beat hemodynamic realities differ profoundly.

This study advances that paradigm by quantifying the hydraulic energy transferred per pulse through the BWI, complemented by its temporal integration, the CPI. This beat-resolved evaluation reveals how powerful or weak each contraction is—information that average power measures cannot capture. In parallel, the AEI characterizes the vascular impedance opposing this transfer, enabling assessment of ventricular-arterial interaction on a cycle-by-cycle basis (15).

Unlike conventional echocardiography, Doppler variables—such as LVOT VTI, myocardial strain, or cardiac output—that isolate flow or deformation, these energetic indices integrate both displacement and pressure to express the hydraulic energy density of each beat. The concordant behavior of these new and traditional parameters between control and postoperative groups underscores the physiologic coherence of the model and its potential to refine real-time circulatory assessment.

Clinical and research implications

These energetic indices introduce new possibilities for hemodynamic monitoring and clinical decision-making. By quantifying the energy delivered with each cardiac contraction, BWI and CPI provide an objective measure of how effectively the ventricle transfers hydraulic energy to the arterial system. In children following cardiovascular surgery, where conventional markers may not reveal early deterioration (12), a decline in BWI or CPI could signal transition toward a low-energy, low-output state—prompting timely optimization of inotropic therapy or consideration of mechanical support. Conversely, rising values may document recovery and guide weaning decisions. The inclusion of AEI extends this approach beyond myocardial performance to encompass vascular impedance and ventricular-arterial coupling, which strongly influence postoperative stability and circulatory efficiency (15). Collectively, these indices enable a comprehensive evaluation of beat-to-beat ventricular-vascular interaction, linking the energy delivered by each contraction to the load it must overcome.

Because they rely solely on standard echocardiographic and non-invasive arterial pressure data, these parameters are technically accessible and easily implementable. As pediatric and adult intensive-care units adopt advanced, non-invasive hemodynamic technologies (14), BWI, CPI, and AEI could integrate seamlessly into monitoring workflows—bridging the gap between physiologic modeling and bedside care.

The principal strength of this study lies in demonstrating the feasibility and clinical relevance of quantifying cardiac energy transfer non-invasively. The retrospective design enabled systematic evaluation of real-world patients while maintaining physiological consistency and meaningful outcome correlations, supporting the validity of the proposed framework. Limitations include the single-center design and modest sample size inherent to a pilot study. The use of a standardized LVOT area simplifies the calculation but introduces geometric assumptions requiring refinement through three-dimensional or indexed adjustments. Absence of simultaneous invasive data precludes direct comparison with measured cardiac power or systemic vascular resistance, though the internal coherence of the results mitigates this limitation.

Future research should focus on (I) validation against invasive reference standards; (II) establishment of age- and body-size-adjusted reference values and differentials with other populations around the world; and (III) clinical implementation within postoperative monitoring and mechanical support algorithms. Integration into echocardiographic software could enable real-time energetic monitoring in intensive care settings.

Conclusions

This study demonstrates that the BWI, CPI, and AEI—derived from routine, non-invasive measurements—offer an integrated, quantitative description of cardiac energy transfer and vascular impedance.

In children following cardiac surgery, these novel indices detected hemodynamic deterioration and predicted recovery trajectories more accurately and earlier than conventional systolic parameters, including LVEF. By jointly characterizing the energy generated by each contraction (BWI, CPI) and the impedance opposing that transfer (AEI), this framework captures the dynamic interaction between the ventricle and arterial system that defines circulatory efficiency. Its non-invasive nature and physiologic coherence make it suitable for real-time clinical implementation and future automation.

Validated here in a pediatric postoperative model, this energetic-vascular construct extends beyond this context, offering a universal physiologic approach to quantify ventricular-arterial interaction and hemodynamic performance across age groups and disease states. It introduces a new dimension to cardiovascular assessment—one that measures, with each heartbeat, both the energy delivered and the resistance encountered, advancing non-invasive evaluation of cardiac function in critical care.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://shc.amegroups.com/article/view/10.21037/shc-24-30/rc

Data Sharing Statement: Available at https://shc.amegroups.com/article/view/10.21037/shc-24-30/dss

Peer Review File: Available at https://shc.amegroups.com/article/view/10.21037/shc-24-30/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://shc.amegroups.com/article/view/10.21037/shc-24-30/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. Ethical approval was obtained from the Ethics Committee of Fundación Cardiovascular de Colombia (No. CEI-2024-08218). As this analysis used anonymized data from an institutional database, the requirement for informed consent was waived by the committee.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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