Mateusz Spiewak

Comparison of different quantification methods of late gadolinium enhancement in patients with hypertrophic cardiomyopathy

AIM There is no consensus regarding the technique of quantification of late gadolinium enhancement (LGE). The aim of the study was to compare different methods of LGE quantification in patients with hypertrophic cardiomyopathy (HCM). METHODS Cardiac magnetic resonance was performed in 33 patients with HCM. First, LGE was quantified by visual assessment by the team of experienced readers and compared with different thresholding techniques: from 1SD to 6SD above mean signal intensity (SI) of remote myocardium, above 50% of maximal SI of the enhanced area (full-width at half maximum, FWHM) and above peak SI of remote myocardium. RESULTS LGE was present in 25 (78%) of patients. The median mass of LGE varied greatly depending on the quantification method used and was highest with the utilization of 1SD threshold [75.5 g, interquartile range (IQR): 63.3-112.3g] and lowest for FWHM method (8.4 g, IQR: 4.3-13.3g). There was no difference in mass of LGE as assessed with 6SD threshold and FWHM when compared to visual assessment (p=0.19 and p=0.1, respectively); all other thresholding techniques provided significant differences in the median LGE size when compared to visual analysis. Results for all thresholds, except FWHM were significantly correlated with visual assessment with the strongest correlation for 6SD (rho=0.956, p<0.0001). CONCLUSIONS LGE quantification with the use of a threshold of 6SD above the mean SI of the remote myocardium provided the best agreement with visual assessment in patients with HCM.

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.

The value of cardiac magnetic resonance and distribution of late gadolinium enhancement for risk stratification of sudden cardiac death in patients with hypertrophic cardiomyopathy

BACKGROUND The presence of late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM) is associated with worse clinical outcome and the extent of LGE predicts the increased risk of sudden cardiac death (SCD). Limited data exist regarding the distribution of LGE. We attempted to verify whether the presence of LGE outside the interventricular insertion points carries additional risk for patients with HCM. METHODS In this prospective study, 328 patients with HCM, who underwent cardiac magnetic resonance (CMR) were enrolled. Five major risk factors for SCD were assessed in all patients. The median follow-up was 37 months. RESULTS LGE was detected in 226 (68.9%) patients. In 70 (21.3%) patients it was present only at the interventricular insertion points - LGE (+) group, while in 156 (47.6%) it was noted in other locations - LGE (++) group. Primary endpoint defined as SCD or appropriate implantable cardioverter-defibrillator intervention occurred in 14 (4.3%) patients, one in LGE (+) and 13 in LGE (++). In multivariable analysis including five traditional risk factors and left ventricular ejection fraction <50%, only the presence of LGE outside the insertion points was a significant predictor of SCD/aborted SCD (HR 10.01, 95% CI 1.21-83.86, p=0.033). The performance of the multivariable sudden cardiac death risk model was improved by the addition of LGE (++) to the traditional risk factors (likelihood ratio p=0.005). The Kaplan-Meier curves showed better event-free survival in the LGE (-) and LGE (+) patient groups compared to the LGE (++) group. CONCLUSIONS In HCM patients, presence of LGE outside interventricular insertion points is associated with increased risk of sudden cardiac death or its equivalent as well as overall mortality. Cardiac fibrosis as a substrate for SCD in HCM may be identified on CMR and serve as an imaging biomarker of increased risk.

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.

Right ventricular outflow tract obstruction should be considered in assessing influence of pulmonary regurgitation on right ventricular volume

We read with interest the results of the study by Wald et al. 1 indicating differences in quantitative assessment of pulmonary regurgitation (PR) with the use of PR fraction and volume. Pulmonary regurgitation volume showed …

Clinical and echocardiographic parameters as risk factors for atrial fibrillation in patients with hypertrophic cardiomyopathy

Atrial fibrillation (AF) is a common complication in patients with hypertrophic cardiomyopathy (HCM) and may contribute to high cardiovascular morbidity and mortality. Therefore, it is important to assess parameters associated with AF in HCM patients.

Challenging Diagnosis of Myocardial Infarction Due to Anomalous Left Circumflex Artery

DOI: 10.5935/abc.20180093 A 45-year-old male without past medical history presented with retrosternal chest pain and ST-segment elevation in inferolateral leads at ECG. Invasive coronary angiography, along with optical coherence tomography performed as part of the clinical study, showed normal coronaries, and myocardial infarction with non-obstructive coronary arteries (MINOCA) was diagnosed (Figure 1 A-B). Due to ongoing chest pain, triple-rule-out computed tomography angiography (CTA) was undertaken to exclude aortic dissection and pulmonary embolism. Incidentally, anomalous left circumflex artery (LCx) originating from the right sinus of Valsalva with a suspicion on severe stenosis was detected (Figure 1 C-E). Selective angiography of the LCx confirmed severe lesion in the distal vessel segment (Figure 1 F), however given the resolution of patient’s symptoms, a decision on medical therapy with dual antiplatelet agents was undertaken. At discharge, cardiac magnetic resonance disclosed mildly reduced left ventricular ejection fraction (53%) with myocardial edema and transmural infarction of the basal-to-mid lateral wall (Figure 1 G-H). LCx arising from the right aortic sinus is the most frequent coronary artery anomaly (CAA) found in up to 0.7% of the population. Although anomalous LCx is considered benign, the severe angle and tortuous vessel course may predispose it to accelerated atherosclerosis. Herein, the anomalous LCx was overlooked due to super-selective cannulation of the right coronary artery, and a large intermediate branch was incorrectly classified as LCx leading to deferred revascularization and irreversible myocardial injury. This case highlights that CAA could be included in the differential diagnosis of MINOCA, and unveils the potential for triple-rule-out CTA in detecting CAA.

Left ventricular diastolic function assessed with cardiovascular magnetic resonance imaging and exercise capacity in patients with non-obstructive hypertrophic cardiomyopathy

BACKGROUND In patients with non-obstructive hypertrophic cardiomyopathy (HCM) and preserved left ventricular (LV) systolic function, diastolic dysfunction is one of the major factors contributing to limited exercise capacity. Cardiovascular magnetic resonance (CMR) imaging has become a useful tool in diagnosis, risk stratification and treatment monitoring in patients with HCM. AIM To assess the relationship between simple CMR parameters of LV diastolic function at rest and exercise capacity measured by means of cardiopulmonary exercise testing on a treadmill in patients with non-obstructive HCM and preserved LV systolic function. METHODS The study included 13 patients with non-obstructive HCM and preserved LV systolic function who underwent cardiopulmonary exercise testing on a treadmill and CMR within 1 month. Analysed parameters of diastolic function included: LV mass index (LVMI), peak filling rate normalised to LV stroke volume index (PFR/LVSVI) and time from the end-systole to PFR normalised to heart rhythm (TPFR). RESULTS There was a significant correlation between PFR/LVSVI at rest and peak oxygen uptake (V02peak) (r=0.64, p=0.02). Patients with V02peak below median (<30 ml/kg/min) had a significantly lower PFR/LVSVI than patients with higher V02peak [5.12 m2/s, interquartile range (IQR) 4.16-6.82 vs. 7.93 m2/s, IQR 7.49-8.21 respectively, p=0.035]. LVMI, TPFR were not related to exercise capacity. There was also no correlation between V02peak and age (r=-0.38, p=0.19), LV ejection fraction (r=-0.36, p=0.22) or normalised LV volume indices: LVEDVI (r=0.09, p=0.76), LVESVI (r=0.34, p=0.26). CONCLUSIONS Assessment of LV diastolic function by peak filling rate normalised to stroke volume index by means of CMR at rest in patients with non-obstructive HCM and preserved LV systolic function is a useful marker of exercise capacity.