Challenges and pitfalls in classification of disproportionate mitral regurgitation.

The concept of disproportionate mitral regurgitation (dispropMR) has been introduced to identify patients with functional mitral regurgitation (MR) who benefit from percutaneous treatment. We aimed to examine echocardiographic characteristics behind this entity. We retrospectively included 172 consecutive patients with reduced left ventricular ejection fraction (LVEF), and more than mild MR referred to clinically indicated echocardiography. According to the proportionality ratio (effective regurgitant orifice area (EROA)/left ventricular end-diastolic volume (LVEDV)) patients were divided into dispropMR and proportionate MR (propMR) group. Potential factors which might affect proportionality definition were analyzed. 55 patients (32%) had dispropMR. Discrepant grading of MR severity was observed when using regurgitant volume (RegVol) by proximal isovelocity surface area (PISA) method or volumetric method, with significant discordance only in dispropMR (p < 0.001). Patients with dispropMR had more frequently left ventricular foreshortened images for LVEDV calculation than patients with propMR (p = 0.003), resulting in smaller LVEDV in dispropMR group. DispropMR group had more substantial dynamic variation of regurgitant flow compared to propMR. Accordingly, EROA was consistently overestimated by standard single-point PISA method compared to serial PISA method. This was more pronounced in dispropMR (bias:10.5 ± 28.3 mm2) compared to propMR group (bias:6.4 ± 12.8 mm2). DispropMR may be found in roughly one third of clinically indicated echocardiographic studies in patients with reduced LVEF and more than mild MR. EROA overestimation due to dynamic variation of regurgitant flow and LVEDV underestimation due to LV foreshortening were more frequently found in dispropMR. Our results indicate that methodological limitations of echocardiographic MR grading could not be neglected in classifying the proportionality of MR.

A novel splice-site FHOD3 founder variant is a common cause of hypertrophic cardiomyopathy in the population of the Balkans-A cohort study.

Founder variants in sarcomere protein genes account for a significant proportion of disease-causing variants in patients with hypertrophic cardiomyopathy (HCM). However, information on founder variants in non-sarcomeric protein genes, such as FHOD3, which have only recently been associated with HCM, remains scarce. In this study, we conducted a retrospective analysis of exome sequencing data of 134 probands with HCM for recurrent pathogenic variants. We discovered a novel likely pathogenic variant c.1646+2T>C in FHOD3 in heterozygous state in eight probands with HCM and confirmed its presence in seven additional relatives. Individuals with this variant had a wide range of ages at onset of the disease (4-63 years). No adverse cardiac events were observed. Haplotype analysis revealed that the individuals with this variant shared a genomic region of approximately 5 Mbp surrounding the variant, confirming the founder effect of the variant. FHOD3 c.1646+2T>C is estimated to have arisen 58 generations ago (95% CI: 45-81) in a common ancestor living on the Balkans. A founder FHOD3 c.1646+2T>C variant is the second most common genetic variant in our cohort of patients with HCM, occurring in 16% of probands with a known genetic cause of HCM, which represents a substantially higher proportion than the currently estimated 0.5-2% for causal FHOD3 variants. Our study broadens the understanding of the genetic causes of HCM and may improve the diagnosis of this condition, particularly in patients from the Balkans.

Role of Exercise Stress Echocardiography in Pulmonary Hypertension.

Resting and exercise right heart catheterisation is the gold standard method to diagnose and differentiate types of pulmonary hypertension (PH). As it carries technical challenges, the question arises if non-invasive exercise stress echocardiography may be used as an alternative. Exercise echocardiography can unmask exercise PH, detect the early stages of left ventricular diastolic dysfunction, and, therefore, differentiate between pre- and post-capillary PH. Regardless of the underlying aetiology, a developed PH is associated with increased mortality. Parameters of overt right ventricle (RV) dysfunction, including RV dilation, reduced RV ejection fraction, and elevated right-sided filling pressures, are detectable with resting echocardiography and are associated with worse outcome. However, these measures all fail to identify occult RV dysfunction. Echocardiographic measures of RV contractile reserve during exercise echocardiography are very promising and provide incremental prognostic information on clinical outcome. In this paper, we review pulmonary haemodynamic response to exercise, briefly describe the modalities for assessing pulmonary haemodynamics, and discuss in depth the contemporary key clinical application of exercise stress echocardiography in patients with PH.

Predicting VO2max in competitive cyclists: Is the FRIEND equation the optimal choice?

Predicting VO2max in athletes is vital for determining endurance capacity, for performance monitoring, in clinical diagnostic procedures, and for disease management. This study aimed to assess the most suitable equation for predicting VO2max in competitive cyclists. Competitive cyclists (496 males, 84 females, Caucasian, 580 total) were included in the study from 1 January 2014 to 31 December 2019. Only subjects who were actively participating in national or international competitions and who were registered competitive cyclists and part of cycling teams at the time of the measurements were included. Subjects performed an incremental test on a cycle ergometer, and VO2max was measured as indicated by a plateau in VO2. In addition, four prediction equations (the FRIEND, Storer, Fairbarn, and Jones) were used to estimate VO2max. The predicted VO2max using the FRIEND equation was in good agreement with the measured VO2max in male and female athletes. This was reflected by a high correlation with r = 0.684 for men and r = 0.897 for women (p = 0.000), with ICC = 0.568 (95% CI 0.184, 0.752) for men and ICC = 0.881 (95% CI 0.813, 0.923) for women. Total error was 1.56 and 1.48 ml/min/kg and a minimal bias of-3.6 and -1.1 ml/min/kg (men and women, respectively). Using other equations resulted in a slight decline in agreement with the measured standard. The FRIEND equation predicted VO2max accurately with small total error, small prediction errors, and with the smallest constant error in our study cohort, indicating the potential value of using FRIEND equation also in competitive cyclists. This equation proved to have the highest accuracy both in male and female cyclists.

Prediction of Maximal Oxygen Consumption in Cycle Ergometry in Competitive Cyclists.

Models for predicting maximal oxygen consumption (VO2max) in average adults might not be suitable for athletes, especially for competitive cyclists who can have significantly higher VO2max than normally active people. The aim of this study was to develop a clinically applicable equation for predicting VO2max during cycle ergometry in competitive cyclists and to compare its accuracy to the traditional American College of Sports Medicine (ACSM) equation. Maximal cycle ergometry tests were performed in 496 male and 84 female competitive cyclists. Six predictors were initially used to model the prediction equation (power output, body weight, body height, fat mass, fat-free mass and age). Power output and body weight were the most important parameters in the model predicting VO2max. Three new equations were derived: for male (VO2max = 0.10 × PO - 0.60 × BW + 64.21), female cyclists (0.13 × PO - 0.83 × BW + 64.02) and the non-gender-specific formula (0.12 × PO - 0.65 × BW + 59.78). The ACSM underestimated VO2max in men by 7.32 mL/min/kg (11.54%), in women by 8.24 mL/min/kg (15.04%) and in all participants by 7.45 mL/min/kg (11.99%), compared to the new equation that underestimated VO2max in men by 0.12 mL/min/kg (0.19%) and in all participants by 0.65 mL/min/kg (1.04%). In female cyclists, the new equation had no relative bias. We recommend that medicine and sports practitioners adapt our proposed equations when working with competitive cyclists. Our findings demonstrate the need to evaluate prediction models for other athletes with a special focus on disciplines that demand high aerobic capacity.

EACVI survey on hypertrophic cardiomyopathy.

AIMS: The European Association of Cardiovascular Imaging (EACVI) Scientific Initiatives Committee performed a global survey to evaluate current practice for the assessment and management of patients with hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: A total of 213 centres from 38 different countries (87% European) responded to the survey. One hundred twenty-one (57%) centres followed HCM patients in a general cardiology outpatient clinic and 85 (40%) centres in a specialized HCM/cardiomyopathy clinic. While echocardiography was the primary imaging modality, cardiovascular magnetic resonance (CMR) has become an important complementary tool. Cardiac anatomy, left ventricular (LV) systolic, and diastolic function were assessed according to current European guidelines and recommendations. To evaluate LV obstruction, 49% of the centres performed bedside provocation manoeuvres in every patient and 55% of the centres used exercise stress echocardiography. The majority of centres used the 5-year risk assessment of sudden cardiac death (SCD) calculated with the HCM Risk-SCD score. However, 34% of the centres also used extensive non-infarct late gadolinium enhancement on CMR and 27% the presence of LV apical aneurysm to help select patients for primary prevention implantable cardioverter-defibrillator therapy. Ninety-nine percent of the responding centres performed regular imaging follow-up of HCM patients. CONCLUSION: Most centres followed European guidelines and recommendations for the diagnosis and management of patients with HCM. The importance of bedside provocation manoeuvres and exercise stress echocardiography to diagnose LV outflow obstruction requires emphasis. Additional risk markers for SCD are used in many centres and might indicate the need for an update of current European recommendations.

Dynamic changes in cardiac function before and early postdelivery in women with severe preeclampsia.

OBJECTIVES: In women with severe preeclampsia the period immediately before and early postdelivery carries the greatest risk for cardiac decompensation due to acute changes in loading conditions. The authors aimed to evaluate dynamic changes in hemodynamic and echocardiographic-derived systolic and diastolic function parameters in preeclamptic women compared with healthy controls. METHODS: Thirty women with severe preeclampsia and 30 healthy controls underwent transthoracic echocardiography 1 day before, 1 and 4 days postdelivery. Fluid responsiveness was assessed by passive leg raising. RESULTS: Peak systolic myocardial velocities (s') and global longitudinal strain (GLS) were significantly lower in preeclamptic group compared with controls only postdelivery (s': 7.3 ±â€Š0.8 vs. 8.3 ±â€Š0.9 cm/s, P < 0.001; GLS: -21.4 ±â€Š2.0 vs. -23.0 ±â€Š1.4%, P = 0.027). In addition, significant decrease in s' after delivery was observed only in preeclamptic group (P = 0.004). For diastolic parameters there were differences both before and postdelivery in E/e' ratio (before: 8.4 ±â€Š2.16 vs. 6.7 ±â€Š1.89, P = 0.002; postdelivery: 8.3 ±â€Š1.64 vs. 6.8 ±â€Š1.27, P = 0.003) and mitral e' velocity (before: 11.0 ±â€Š2.39 vs. 12.6 ±â€Š1.86, P = 0.004; postdelivery: 11.1 ±â€Š2.28 vs. 14.0 ±â€Š2.40 cm/s, P < 0.001). Significant increase in left ventricular stroke volume (P = 0.005) and transmitral E velocity (P = 0.003) was observed only in control group, reflecting response to volume load after delivery. Accordingly, only the minority of preeclamptic women were fluid responsive (11 vs. 43%, P = 0.014 between groups). CONCLUSION: Variations in cardiac parameters in healthy women seem to follow changes in loading conditions before and early after delivery. Different pattern in preeclamptic women, however, may be related to subtle myocardial dysfunction, that becomes uncovered with augmented volume load in early postpartum period.

Improvement of Atrial and Ventricular Remodeling with Low Atrial Fibrillation Burden after Hybrid Ablation of Persistent Atrial Fibrillation.

BACKGROUND: An endoscopic transdiaphragmatic epicardial radiofrequency ablation procedure combined with percutaneous endocardial radiofrequency ablation--a hybrid procedure--is a potentially curative treatment option for patients with persistent atrial fibrillation (AF). Long-term effects of arrhythmia elimination on atrial and ventricular remodeling are not completely understood. Therefore, the aim of our study was to quantify echocardiographic structural and functional changes of the left atrium (LA) and left ventricle (LV) following a hybrid procedure. METHODS AND RESULTS: Thirty-seven consecutive patients with symptomatic drug refractory persistent AF underwent a hybrid procedure to achieve complete pulmonary vein and LA posterior wall electrical isolation. AF burden was measured using an insertable electrocardiographic (ECG) monitor. Patients were divided into responders to ablation and nonresponders according to postoperative AF burden at 12-month follow-up (responder < 0.5% vs nonresponder ≥ 0.5%). Median AF burden was 0.32 (0.04-27.5)% for all patients. In responders (19/37 patients), significant echocardiographic reduction of LA volume index from 47 to 41 mL/m(2) (P < 0.05) and improvement of LA function parameters (LA stiffness from 73.3 to 41.3 [P < 0.05], LA emptying fraction from 21% to 45% [P < 0.05], LA global longitudinal strain from 11.2% to 18.8% [P < 0.5]) was documented. In addition, LV systolic function significantly improved in comparison with nonresponders. CONCLUSION: Hybrid ablation of persistent AF achieved stable sinus rhythm in a significant proportion of patients, as evidenced by continuous ECG monitoring, resulting in important LA and LV reverse remodeling after 12 months.