Magnetic resonance imaging in patients with implanted cardiac electrotherapy devices: a statement from experts of the Polish Medical Society of Radiology, the Polish Society of Cardiology, and the Polish Society of Electroradiology.

The year 2023 marks 60 years since the first pacemaker was implanted in Poland. The number of implantable cardiac electrotherapy devices (CIEDs), including pacemakers, cardioverter-defibrillators, and resynchronization therapy systems, has been systematically increasing in the subsequent decades. It is estimated that nearly 500,000 Poles have an implanted cardiac electrotherapy device, making optimal diagnostic imaging with the use of magnetic resonance imaging (MRI) a clinically and epidemiologically important issue. MRI has become a gold diagnostic standard in many disease states. In this situation, it is believed that 50-70% of patients who have a cardiac electrotherapy device may have indications for an MRI examination later in life. For many years, an implanted cardiac electrotherapy device was considered a definite contraindication to MRI. However, MRI has become possible in most patients with CIED if certain procedures and precautions are followed. In these guidelines, we describe the basic rules that should be followed in order to perform a safe MRI examination in patients with different CIEDs. Despite all the risks and organizational factors described in the text, it seems that for many MRI departments, MRI in patients with CIEDs is achievable and should be implemented immediately. A second important issue is the need for dedicated financial support for these procedures from public health insurance.

Impact of cardiac magnetic resonance on the diagnosis of hypertrophic cardiomyopathy - a 10-year experience with over 1000 patients.

OBJECTIVES: To assess the value of cardiac MRI in comparison to echocardiography in consecutive patients with previously diagnosed and new suspected hypertrophic cardiomyopathy (HCM). METHODS: All MRI studies of patients with HCM or suspected disease performed at our centre within a 10-year time period were evaluated. Initial diagnoses (echocardiography-based) and final (MRI-based) diagnoses were compared in subgroups, and the discrepancies were recorded. RESULTS: A total of 1006 subjects with HCM or suspected HCM were identified (61% males, 39% females; median age, 49.1 years; interquartile range, 34.9-60.4). In 12 (2.2%) out of 550 patients with known HCM, MRI indicated a diagnosis other than HCM, including but not limited to the subaortic membrane (n = 1, 8.3%) or mild left ventricular hypertrophy (n = 5, 41.7%). Among all patients with suspected HCM (n = 456), MRI diagnosis was different from HCM in 5.3% (n = 24) of patients. In an additional 20.4% of patients (n = 93), no significant hypertrophy was present. In total, among patients with suspected HCM, MRI led to clear HCM diagnosis in 204 (44.7%) patients. Among patients with a history of uncontrolled hypertension suspected of having HCM, MRI aided in identifying cardiomyopathy in 47.9% of patients. This subgroup contained the largest proportion of patients with an ambiguous diagnosis, namely, 29.6% compared with 13.8% in the remaining groups of patients with suspected HCM (p = 0.0001). CONCLUSIONS: In a small but important group of patients with ultrasound-based HCM, cardiac MRI can diagnose previously unknown conditions and/or refute suspected cardiomyopathy. The diagnostic yield of MRI when compared to echocardiography in patients suspected of having HCM is 44.7%. KEY POINTS: • Out of 550 patients previously diagnosed with echocardiography but without magnetic resonance imaging (MRI) as having hypertrophic cardiomyopathy (HCM), we diagnosed a different disease in 12 (2.2%) patients using MRI. • Among patients with suspected HCM based on echocardiography, MRI led to clear HCM diagnosis in 44.7% of patients. • In patients with a history of uncontrolled hypertension suspected, based on an echocardiogram, of having HCM, MRI aided in identifying cardiomyopathy in 47.9% of patients. This subgroup contained the largest proportion of patients with an ambiguous diagnosis.

A different background of arrhythmia in siblings with a positive family history of sudden death at young age.

We present two symptomatic sisters who had a positive family history of sudden death. None of them had structural heart disease. In the 25-year-old proband, complex ventricular arrhythmia, cardiac conduction system disease, and skeletal muscle weakness were found. Genetic examination showed a pathogenic intronic variant in the desmin gene in the proband only. In the elder sister with palpitations, complex ventricular arrhythmia (>46 000 ectopic beats) was removed by radiofrequency ablation. This family case shows that complex ventricular arrhythmia may have different background within one family, genetic examinations should be performed in a person with broadest spectrum of symptoms.

The impact of pulmonary regurgitation on right ventricular size and function in patients with repaired tetralogy of Fallot and additional haemodynamic abnormalities.

PURPOSE: Right ventricular (RV) outflow tract obstruction (RVOTO) was demonstrated to be protective against RV dilatation in patients with repaired tetralogy of Fallot and chronic pulmonary regurgitation (PR). We hypothesised that the presence of additional haemodynamic abnormalities (more than mild tricuspid regurgitation, residual ventricular septal defect) reduces this protective association. Accordingly, we aimed to assess the impact of PR on RV size and function in this population. MATERIAL AND METHODS: Consecutive patients with additional haemodynamic abnormalities after tetralogy of Fallot (TOF) repair, who had undergone cardiovascular magnetic resonance, were included. RESULTS: Out of 90 patients studied, 18 individuals (mean age 32.5 ± 10.7 years, 72.2% males) met the inclusion criteria. There were no differences in RV volumes and ejection fraction between patients with and without RVOTO. Neither PR fraction (PRF) nor PR volume (PRV) correlated with RV end-diastolic volume (r = 0.36; p = 0.15 and r = 0.37; p = 0.14, respectively, for PRF and PRV) or RV end-systolic volume (r = 0.2; p = 0.42 and r = 0.19; p = 0.45, respectively, for PRF and PRV). Similarly, no significant correlations were observed between PRF or PRV and RV ejection fraction (r = -0.04; p = 0.87 and r = -0.03; p = 0.9, respectively). CONCLUSIONS: Additional haemodynamic abnormalities are associated with the abolition of the protective effect of RVOTO on RV size. There was no significant relationship between measures of PR and RV volumes in patients after TOF repair with concomitant haemodynamic abnormalities. These abnormalities acted as confounding factors in the assessment of the impact of pulmonary regurgitation on RV size and function.

Biatrial performance in children with hypertrophic cardiomyopathy: CMR study.

OBJECTIVES: To investigate biatrial mechanics and their relation with left ventricular outflow tract (LVOT) obstruction (LVOTO), the degree of hypertrophy, indices of ventricular diastolic function and fibrosis in children with hypertrophic cardiomyopathy (HCM). METHODS: Fifty-five consecutive, prospectively recruited children with HCM (mean age 12.5 ± 4.6 years, 69.1% male), 19 (34.5%) of whom had LVOTO, underwent cardiac magnetic resonance and echocardiography with quantification of phasic components of biatrial function, biventricular diastolic function and fibrosis. Twenty healthy, sex-matched subjects served as controls. RESULTS: We found a significant increase of left atrial (LA) and right atrial (RA) volumes and reduction in the majority of indices of contractile function, strains and strain rates (p < 0.05) in children with HCM compared with controls. Nearly all of the LA dynamics markers attained a significant association with the LVOT gradient (p < 0.05), the RA volumes and contractile functions were affected by LV fibrosis and mass (p < 0.05), and the RA mechanical components were related to the degree of LVOTO (p < 0.05). The minority of biatrial dynamics markers were associated with indices of ventricular diastolic function. CONCLUSIONS: The majority of biatrial volumetric and functional indices were severely compromised in children with HCM compared with controls. The degree of LVOTO appears to trigger LA volumetric and LA and RA mechanical malfunction. On the other hand, the deterioration of RA volumetric components was linked to LV fibrosis and mass. KEY POINTS: • Biatrial function was severely compromised in children with HCM. • Left atrial malfunction was associated with the degree of LVOTO. • Fibrosis and LV mass were related to RA volumetric and contractile dysfunction. • The degree of LVOTO was linked to right atrial mechanical abnormalities.

Circulating biomarkers of hypertrophy and fibrosis in patients with hypertrophic cardiomyopathy assessed by cardiac magnetic resonance.

BACKGROUND: Myocardial fibrosis in hypertrophic cardiomyopathy (HCM) is associated with worse clinical outcomes. The availability of circulating biomarkers of myocardial fibrosis and hypertrophy would be helpful in clinical practice. OBJECTIVE: The aim of this study was to evaluate usefulness of various biomarkers of myocardial fibrosis and hypertrophy in HCM. METHODS: Levels of biomarkers: soluble ST2 (sST2), galectin-3 (Gal-3), growth differentiation factor-15 (GDF-15), NT-proBNP and high-sensitivity cardiac troponin T (hs-cTnT) were measured in 60 patients with HCM. All patients underwent cardiac magnetic resonance imaging to calculate parameters of hypertrophy and fibrosis. RESULTS: We observed positive correlations among sST2 levels and left ventricular mass (LVM) (r = 0.32, p = 0.012), LV mass indexed for the body surface area (LVMI) (r = 0.27, p = 0.036) and maximal wall thickness (MWT) (r = 0.31, p = 0.015). No correlation was found between Gal-3 and GDF-15 levels and hypertrophy and fibrosis parameters. We observed positive correlations among hs-cTnT levels and LVM (r = 0.58, p < 0.0001), LVMI (r = 0.48, p = 0.0001), MWT (r = 0.31, p = 0.015) and late gadolinium enhancement (LGE) mass (r = 0.37, p = 0.003). There were positive correlations between NT-proBNP levels and LVM (r = 0.33, p = 0.01), LVMI (r = 0.41, p = 0.001), MWT (r = 0.42, p < 0.001) and LGE mass (r = 0.44, p < 0.001). CONCLUSIONS: Although no correlation between sST2 levels and myocardial fibrosis was found, sST2 may provide some additional information about hypertrophy extension. NT-proBNP and hs-cTnT are useful biomarkers in assessment of hypertrophy and fibrosis in HCM.

Quantification of mitral regurgitation in patients with hypertrophic cardiomyopathy using aortic and pulmonary flow data: impacts of left ventricular outflow tract obstruction and different left ventricular segmentation methods.

BACKGROUND: Cardiovascular magnetic resonance (CMR) imaging in patients with hypertrophic cardiomyopathy (HCM) enables the assessment of not only left ventricular (LV) hypertrophy and scarring but also the severity of mitral regurgitation. CMR assessment of mitral regurgitation is primarily based on the difference between LV stroke volume (LVSV) and aortic forward flow (Ao) measured using the phase-contrast (PC) technique. However, LV outflow tract (LVOT) obstruction causing turbulent, non-laminar flow in the ascending aorta may impact the accuracy of aortic flow quantification, leading to false conclusions regarding mitral regurgitation severity. Thus, we decided to quantify mitral regurgitation in patients with HCM using Ao or, alternatively, main pulmonary artery forward flow (MPA) for mitral regurgitation volume (MRvol) calculations. METHODS: The analysis included 143 prospectively recruited subjects with HCM and 15 controls. MRvol was calculated as the difference between LVSV computed with either the inclusion (LVSVincl) or exclusion (LVSVexcl) of papillary muscles and trabeculations from the blood pool and either Ao (MRvolAoi or MRvolAoe) or MPA (MRvolMPAi or MRvolMPAe). The presence or absence of LVOT obstruction was determined based on Doppler echocardiography findings. RESULTS: MRvolAoi was higher than MRvolMPAi in HCM patients with LVOT obstruction [47.0 ml, interquartile range (IQR) = 31.5-60.0 vs. 35.5 ml, IQR = 26.0-51.0; p < 0.0001] but not in non-obstructive HCM patients (23.0 ml, IQR = 16.0-32.0 vs. 24.0 ml, IQR = 15.3-32.0; p = 0.26) or controls (18.0 ml, IQR = 14.3-21.8 vs. 20.0 ml, IQR = 14.3-22.0; p = 0.89). In contrast to controls and HCM patients without LVOT obstruction, in HCM patients with LVOT obstruction, aortic flow-based MRvol (MRvolAoi) was higher than pulmonary-based findings (MRvolMPAi) (bias = 9.5 ml; limits of agreement: -11.7-30.7 with a difference of 47 ml in the extreme case). The differences between aortic-based and pulmonary-based MRvol values calculated using LVSVexcl mirrored those derived using LVSVincl. However, MRvol values calculated using LVSVexcl were lower in all the groups analyzed (HCM with LVOT obstruction, HCM without LVOT obstruction, and controls) and with all methods of MRvol quantification used (p ≤ 0.0001 for all comparisons). CONCLUSIONS: In HCM patients, LVOT obstruction significantly affects the estimation of aortic flow, leading to its underestimation and, consequently, to higher MRvol values than those obtained with MPA-based MRvol calculations.

Cine dyscontractility index: A novel marker of mechanical dyssynchrony that predicts response to cardiac resynchronization therapy.

PURPOSE: To investigate whether magnetic resonance imaging (MRI) cine-derived dyssynchrony indices provide additional information compared to conventional tagged MRI (tMRI) acquisitions in heart failure patients undergoing cardiac resynchronization therapy (CRT). MATERIALS AND METHODS: Patients scheduled for CRT (n = 52) underwent preprocedure MRI including cine and tMRI acquisitions. Segmental strain curves were calculated for both cine and tMRI to produce a range of standard indices for direct comparison between modalities. We also proposed and evaluated a novel index of "dyscontractility," which detects the presence of focal areas with paradoxically positive circumferential strain. RESULTS: Across conventional strain indices, there was only moderate-to-poor (R = 0.3-0.6) correlation between modalities; eight cine-derived indices showed statistically significant (P < 0.05) relations to CRT outcome compared to just two tMRI-based counterparts. The novel dyscontractility index calculated on basal slice cine images (cine dyscontractility index, "CDI") was the single best predictor of clinical response to CRT (area under the curve AUC = 0.81, P < 0.001). While poorly correlated to its tMRI counterpart (R = 0.33), CDI performed significantly better in predicting response to CRT (P < 0.005), and was also numerically better than all other tMRI indices (AUC 0.53-0.76, all P for AUC comparisons <0.17). CONCLUSION: Cine-derived strain indices offer potentially new information compared to tMRI. Specifically, the novel CDI is most strongly linked to response to cardiac resynchronization therapy in a contemporary patient cohort. It utilizes readily available MRI data, is relatively straightforward to process, and compares favorably with any conventional tagging index. J. Magn. Reson. Imaging 2016;44:1483-1492.

Does p.Q247X in TRIM63 cause human hypertrophic cardiomyopathy?

RATIONALE: Variants in TRIM63, including a nonsense mutation (p.Q247X), have been suggested recently to cause hypertrophic cardiomyopathy. OBJECTIVE: To verify pathogenicity of TRIM63 p.Q247X detected by whole-exome sequencing in a symptomless professional sports player seeking medical advice because of a prolonged QT interval found during a routine check-up. METHODS AND RESULTS: Clinical studies were performed in the proband and his mother, who also carried TRIM63 p.Q247X. No evidence of hypertrophic cardiomyopathy was found in either person. CONCLUSIONS: The p.Q247X variant in TRIM63 is not likely to be a highly penetrant variant causing hypertrophic cardiomyopathy.

Percutaneous Edwards SAPIEN(™) valve implantation for significant pulmonary regurgitation after previous surgical repair with a right ventricular outflow patch.

BACKGROUND: Current indications for percutaneous pulmonary valve implantation (PPVI) are limited to patients who had their outflow tracts repaired with the use of a "full" condui-homograft. Patients after a patch repair are believed to have an unfavorable anatomy for PPVI. OBJECTIVES: To evaluate a novel use of Edwards SAPIEN(TM) valve for percutaneous treatment of moderate and severe pulmonary regurgitation after tetralogy of Fallot (TF) repair with a right ventricular outflow (RVOT) patch. METHODS: PPVI was intended in 10 patients (age 21-39 years, 2 ♂) with regurgitant fraction of 30-59%, measured by cardiac magnetic resonance imaging (CMRI) 16-30 years after repair with a RVOT patch. Balloon test-inflations were used for definitive measurements and location of the landing site for the valve. All RVOTs were prestented. RESULTS: Successful valve implantation was achieved in nine patients. In one patient a bare-metal stent used for prestenting embolized into pulmonary artery. A 26-mm valve was implanted in seven and a 23-mm in two patients. CMRI at 1-2 month follow-up (n = 8) demonstrated both, sustained relief of pulmonary incompetence (regurgitant fraction = 0-14%) and significant decrease of the right ventricular end-diastolic volume indexes (from 169.9 ± 43.8 to 140.0 ± 40.3 ml/m(2) , P < 0.001). At that follow-up no adverse event occurred. No stent fractures were observed. CONCLUSIONS: We report the first case series of patients with significant PR after a RVOT patch repair, successfully treated with a percutaneous Edwards SAPIEN(TM) valve implantation. The procedure is technically feasible and may be offered to patients with the outflow tracts larger than those limited by the Melody(®) system available currently.

Electrocardiographic characteristics of the right ventricle following hemodynamic improvement after percutaneous pulmonary valve implantation, one year follow-up.

Percutaneous pulmonary valve implantation (PPVI) is an alternative to open-heart surgery in patients with congenital heart defect. The purpose of the study is to evaluate right ventricle (RV) electrocardiographic characteristics in relation with hemodynamic changes after PPVI. In 30 patients (16 males, aged 24±7years), ECG RV characteristics changes (R amplitude in V1 and aVR, Sokolow-Lyon index (SL) for RV hypertrophy, QRS duration) from before and 1year after PPVI were correlated with changes in RV end-diastolic volume (RVEDV), RV end-systolic volume (RVESV), RV ejection fraction (RVEF), RV mass in cardiac magnetic resonance (cMRI) and within pulmonary gradient in echocardiography. Significant correlations were observed: decrease R amplitude in aVR correlated to decrease RVESV and RV mass; decrease RVESV and pulmonary gradient to reduction in SL-V5; increase RVEF to reduction R aVR and SL-V5. Improvement of hemodynamic parameters in cMRI and echocardiography is parallel to that of electrocardiographic criteria of RV hypertrophy.

Impact of Cardiac Magnetic Resonance on the Diagnosis of Left Ventricular Noncompaction-A 15-Year Experience.

The aim of this study was to assess the impact of cardiac magnetic resonance (CMR) on the diagnosis in patients with known or suspected left ventricular noncompaction (LVNC). We retrospectively reviewed the medical charts of 12,811 consecutive patients who had CMR studies between 2008 and 2022 in a large tertiary center. We included patients referred for CMR because of known or suspected LVNC. The study sample consisted of 333 patients, 193 (58.0%) male, median age 39.0 (26.8-51.0) years. Among 74 patients fulfilling the echocardiographic LVNC criteria, the diagnosis was confirmed in 54 (73.0%) cases. In 259 patients with ultrasound-based suspicion of LVNC, CMR led to an LVNC diagnosis in 82 (31.7%) patients. In both groups, CMR led to a new diagnosis in 89 cases (10 (13.5%) and 79 (30.5%)). A quantity of 38 (5.4%) patients were diagnosed with dilated cardiomyopathy, 11 (1.4%) patients were diagnosed with hypertrophic cardiomyopathy, and 21 (4.1%) patients were diagnosed with unclassified cardiomyopathy. In four patients with suspected LVNC, a myocardial trabeculation was a secondary result of dilatation due to coronary heart disease. In five cases, valvular heart disease was found. Four patients were diagnosed with athlete's heart. Other diagnoses (arrhythmogenic right ventricular cardiomyopathy, peripartum cardiomyopathy, hypokinetic non-dilated cardiomyopathy, sarcoidosis, amyloidosis, and ventricular septum defect) were found in six patients. CMR is a valuable tool in the evaluation of cardiac muscle and in differentiating LVNC and other cardiac diseases.

Malignant Hypertension:A Systemic Cardiovascular Disease: JACC Review Topic of the Week.

Malignant hypertension (MHT) is a hypertensive emergency with excessive blood pressure (BP) elevation and accelerated disease progression. MHT is characterized by acute microvascular damage and autoregulation failure affecting the retina, brain, heart, kidney, and vascular tree. BP must be lowered within hours to mitigate patient risk. Both absolute BP levels and the pace of BP rise determine risk of target-organ damage. Nonadherence to the antihypertensive regimen remains the most common cause for MHT, although antiangiogenic and immunosuppressant therapy can also trigger hypertensive emergencies. Depending on the clinical presentation, parenteral or oral therapy can be used to initiate BP lowering. Evidence-based outcome data are spotty or lacking in MHT. With effective treatment, the prognosis for MHT has improved; however, patients remain at high risk of adverse cardiovascular and kidney outcomes. In this review, we summarize current viewpoints on the epidemiology, pathogenesis, and management of MHT; highlight research gaps; and propose strategies to improve outcomes.

Isolated myocardial edema in cardiac magnetic resonance - in search of a management strategy.

Isolated myocardial edema not accompanied by late gadolinium enhancement (LGE) may be occasionally found on cardiac magnetic resonance (CMR). This type of picture may be encountered in patients with suspected myocarditis, post some acute cardiac events, with cardiac allograft rejection or even in athletes after an extreme exercise. Currently, there is no clear management strategy for this type of incidental finding. In this narrative review we discuss the methods and pitfalls of edema detection with means of CMR, review published data on isolated myocardial edema for each of the most probable clinical scenarios and propose a structured clinical decision-making algorithm to help clinicians navigate through this type of CMR result. Finally, we highlight the most important gaps in evidence related to isolated myocardial edema without fibrosis, where further research is particularly needed.

Advanced Cardiac Imaging in the Assessment of Aortic Stenosis.

Aortic stenosis is the most common form of valve disease in the Western world and a major healthcare burden. Although echocardiography remains the central modality for the diagnosis and assessment of aortic stenosis, recently, advanced cardiac imaging with cardiovascular magnetic resonance, computed tomography, and positron emission tomography have provided invaluable pathological insights that may guide the personalized management of the disease. In this review, we discuss applications of these novel non-invasive imaging modalities for establishing the diagnosis, monitoring disease progression, and eventually planning the invasive treatment of aortic stenosis.

A distinct septal pattern of late gadolinium enhancement specific for COVID-induced myocarditis: A multicenter cardiovascular magnetic resonance study.

BACKGROUND: COVID-19 is a great medical challenge as it provokes acute respiratory distress and has pulmonary manifestations and cardiovascular (CV) consequences. AIMS: This study compared cardiac injury in COVID-19 myocarditis patients with non-COVID-19 myocarditis patients. METHODS: Patients who recovered from COVID-19 were scheduled for cardiovascular magnetic resonance (CMR) owing to clinical myocarditis suspicion. The retrospective non-COVID-19 myocarditis (2018-2019) group was enrolled (n = 221 patients). All patients underwent contrast-enhanced CMR, the conventional myocarditis protocol, and late gadolinium enhancement (LGE). The COVID study group included 552 patients at a mean (standard deviation [SD]) age of 45.9 (12.6) years. RESULTS: CMR assessment confirmed myocarditis-like LGE in 46% of the cases (68.5% of the segments with LGE <25% transmural extent), left ventricular (LV) dilatation in 10%, and systolic dysfunction in 16% of cases. The COVID-19 myocarditis group showed a smaller median (interquartile range [IQR]) LV LGE (4.4% [2.9%-8.1%] vs. 5.9% [4.4%-11.8%]; P <0.001), lower LV end-diastolic volume (144.6 [125.5-178] ml vs. 162.8 [136.6-194] ml; P <0.001), limited functional consequence (left ventricular ejection fraction, 59% [54.1%-65%] vs. 58% [52%-63%]; P = 0.01), and a higher rate of pericarditis (13.6% vs. 6%; P = 0.03) compared to non-COVID-19 myocarditis. The COVID-19-induced injury was more frequent in septal segments (2, 3, 14), and non-COVID-19 myocarditis showed higher affinity to lateral wall segments (P <0.01). Neither obesity nor age was associated with LV injury or remodeling in subjects with COVID-19 myocarditis. CONCLUSIONS: COVID-19-induced myocarditis is associated with minor LV injury with a significantly more frequent septal pattern and a higher pericarditis rate than non-COVID-19 myocarditis.

Repaired tetralogy of Fallot: ratio of right ventricular volume to left ventricular volume as a marker of right ventricular dilatation.

PURPOSE: To compare indexed right ventricular (RV) end-diastolic volume (RVEDVi) and the ratio of RV volume to left ventricular (LV) volume (RV/LV ratio) in prediction of significant pulmonary regurgitation (PR) after tetralogy of Fallot (TOF) repair and to assess sex differences in the RV/LV ratio. MATERIALS AND METHODS: The ethics committee approved this retrospective single-center study, and patients or their parents or guardians signed written informed consent. RVEDVi, RV/LV ratio, and PR were measured with the use of magnetic resonance imaging in 155 consecutive patients with repaired TOF (mean age, 29.2 years±10.9 [standard deviation]; 98 [63.2%] male and 57 [36.8%] female patients). PR fraction of 20% or greater was considered significant. The capability of the RVEDVi and that of the RV/LV ratio for prediction of significant PR were compared by using logistic regression analysis and receiver operating characteristic curve analysis. RESULTS: RVEDVi was significantly higher in male (162.8 mL/m2±50.4) than in female (138.2 mL/m2±37.5) patients (P=.001). Conversely, the RV/LV ratio was similar in both sexes (1.82±0.56 [male] vs 1.69±0.46 [female], P=.13) both in the entire cohort and after excluding patients with significant (≥30 mm Hg) RV outflow tract gradient and/or other residual hemodynamic abnormalities (P=.63). Receiver operating characteristic analysis revealed better discrimination of significant (≥20%) from insignificant (<20%) PR with the use of the RV/LV ratio than with RVEDVi (area under the receiver operating characteristic curve, 0.937 [model 4] vs 0.849 [model 1], P=.01). In multivariate analysis, the only independent predictor of PR fraction was the RV/LV ratio. CONCLUSION: The RV/LV ratio is more accurate than the RVEDVi in differentiation of significant from insignificant PR. After TOF repair, female and male patients have similar RV/LV ratios despite significant differences in RVEDVi between the sexes.