Global longitudinal strain detects subtle left ventricular systolic dysfunction in Duchenne muscular dystrophy patients and carriers.

BACKGROUND: With the continuous improvement of the respiratory care of Duchenne muscular dystrophy patients, cardiac manifestations (heart failure and arrhythmias) become the leading causes of morbidity and mortality. Early identification of cardiac muscle affection is crucial to start anti-failure drugs that reverse remodeling and improve prognosis. This study aimed to detect subtle cardiac changes in Duchenne muscular dystrophy patients and carriers using electrocardiography and echocardiography. RESULTS: This study included genetically diagnosed Duchenne muscular dystrophy patients (28 males) and carriers (25 females) and compared them to healthy gender-matched control groups. All study participants underwent clinical assessment, 12-lead electrocardiography, and global longitudinal strain augmented echocardiography. In the current study, Duchenne muscular dystrophy patients had higher heart rates, smaller left ventricular internal diameters, left atrial diameter, lower ejection fraction, and worse left ventricular global longitudinal strain in comparison with the control group. The global longitudinal strain inversely correlated with the age of Duchenne muscular dystrophy patients. The number of exon mutations did not affect electrocardiography and echocardiographic findings. Exon mutations 45-47 and 51-54 were significantly associated with an ejection fraction less than 60%. Duchenne muscular dystrophy carriers had smaller left ventricular wall diameters, left ventricular end-diastolic diameter, left atrial diameter, and worse left ventricular global longitudinal strain in comparison with the control group. CONCLUSIONS: Left ventricular global longitudinal strain could detect subtle left ventricular systolic dysfunction in Duchenne muscular dystrophy patients and carriers before the decline of left ventricular ejection fraction.

Assessing the impact of a combination of sofosbuvir and daclatasvir treatment for hepatitis C virus infection on heart rate, rhythm and heart rate variability using 24-hour ECG monitoring.

BACKGROUND: Direct-acting antiviral agents (DAAs) cure patients with hepatitis C virus (HCV) infection. Concerns have arisen the occurrence of significant bradyarrhythmias during treatment with DAAs. The aim of this study was to assess the impact of a DAA combination for the treatment of HCV infection on heart rate, rhythm, and heart rate variability (HRV) using 24-h ECG monitoring. RESULTS: A prospective randomized study of 50 treatment-naïve patients with HCV infection treated with a combination of sofosbuvir 400 mg daily and daclatasvir 60 mg daily for 12 weeks. Surface ECG and 24-h ECG monitoring were performed at baseline and after completion of therapy to assess PR interval, corrected QT interval (QTc), minimum heart rate (HR), maximum HR, average HR, HRV time-domain and frequency-domain measures, significant pauses, tachycardias, bradycardias, premature atrial contractions (PACs), and premature ventricular contraction (PVCs). No differences were detected in all examined parameters between baseline and after completion of treatment. PR interval was 154 ± 25.95 vs 151.4 ± 23.82 ms, respectively (p = 0.124). QTc interval was 397.34 ± 29.38 vs 395.04 ± 30.23 ms, respectively (p = 0.403). No differences were detected for minimum HR, maximum HR, average HR, HRV time-domain and frequency-domain measures, the occurrence of significant pauses, sinus tachycardia episodes, sinus bradycardia episodes, PACs, and PVCs. No episodes of bradyarrhythmias, syncope, and atrial fibrillation, supraventricular, or ventricular tachycardias were reported or detected. CONCLUSION: In non-cardiac patients receiving no cardioactive medications, the combination of sofosbuvir and daclatasvir for the treatment of HCV infection has no effect on HR, rhythm, conductivity, or HRV. No symptomatic bradycardias, tachycardias, or syncope were reported or detected using 24-h ECG monitoring.

Resting myocardial velocity gradient is a reliable measurement that identifies viable myocardium.

UNLABELLED: In the setting of coronary artery disease, two-thirds of LV dysfunction is not the result of irreversible scar, but rather caused by impairment in function and energy use of "still-viable" myocyte. The opportunity for improved function, if coronary blood flow is restored, is there which makes the identification of viable myocardium important. PURPOSE: The purpose of this study is to identify the value of resting myocardial velocity gradient (MVG) in detecting viable myocardium in patients with healed anterior wall myocardial infarction (MI). PATIENTS AND METHODS: The study included 30 patients with healed anterior MI, who were submitted to conventional echocardiography and tissue Doppler for measurement of MVG. Myocardial perfusion scan using Technetium (Tc)-99m was the gold standard test for the detection of viability. Ten healthy control subjects were also included to obtain reference values for MVG. RESULTS: Resting MVG was able to differentiate infarct regions, and to detect viable myocardium compared to Tc-99m studies (0.68 +/- 0.2 vs 0.49 +/- 0.22) P < 0.01. CONCLUSION: MVG provides quantitative assessment of the regional wall thickening that help localizing the infarct zone and detecting viable myocardium at rest.