Prolonged QT predicts prognosis in COVID-19.

Background: Coronavirus disease-2019 (COVID-19) causes severe illness and multi-organ dysfunction. An abnormal electrocardiogram is associated with poor outcome, and QT prolongation during the illness has been linked to pharmacological effects. This study sought to investigate the effects of the COVID-19 illness on the corrected QT interval (QTc).

Current practices of Asia-Pacific cardiologists in the utilization of bioresorbable scaffolds.

Background & Aims: Although Absorb Bioresorbable Vascular Scaffolds (A-BVS) are routinely used in the Asia-Pacific, there is little information on patient selection or deployment technique here. This document investigates the experiences of leading interventional cardiologists from the Asia-Pacific region with a focus on patient characteristics, deployment techniques and management.

Methods And Results: A detailed questionnaire was distributed to 28 highly-experienced interventional cardiologists ('Authors') from 13 Asia-Pacific countries.

P-wave abnormality predicts recurrence of atrial fibrillation after electrical cardioversion: a prospective study.

Background: Maintenance of atrial fibrillation (AF) is related to atrial electrical inhomogeneity and resultant chaotic reentry. Our aim was to test the hypothesis that abnormalities of P morphology on the surface electrocardiogram (ECG) predict recurrent AF following electrical cardioversion (ECV).

Methods: A 12-lead ECG was recorded after ECV for persistent AF in 77 patients (51 men, 65 ± 10 years) and repeated 1 month later.

T-wave alternans and left ventricular wall thickness in predicting arrhythmic risk in patients with hypertrophic cardiomyopathy.

Background: Regional heterogeneity of left ventricular (LV) hypertrophy may contribute to arrhythmic vulnerability in patients with hypertrophic cardiomyopathy (HCM). The aim of the present study was to investigate the relationship between LV wall thickness (LVWT) and microvolt T-wave alternans (TWA), a surrogate risk marker of ventricular tachyarrhythmias (VTAs).

Methods And Results: A total of 157 consecutive HCM patients underwent 2-D echocardiography and TWA-exercise testing, and assessment of arrhythmic burden in a follow up of a median 3.

Significance of maximal and regional left ventricular wall thickness in association with arrhythmic events in patients with hypertrophic cardiomyopathy.

Background: Increased maximal left ventricular wall thickness (LVWT; >30 mm) is a marker of risk for sudden cardiac death in hypertrophic cardiomyopathy (HCM). Patients with mild left ventricular hypertrophy (LVH) are not free of events. Regional heterogeneity of LVH may contribute to arrhythmic vulnerability.

Drug-induced Brugada syndrome.

Brugada syndrome is an inherited cardiac arrhythmia condition characterized by (i) coved ST-elevation and J point elevation of at least 2 mm in at least two of the right precordial ECG leads (V1-V3) and (ii) ventricular arrhythmias, syncope, and sudden death. Patients with Brugada syndrome or suspected mutation carriers can have normal ECG recordings at other times. In these cases, a diagnostic challenge with a sodium channel blocker such as ajmaline, flecainide, or pilsicainide may induce the full-blown type 1 ECG pattern and support the diagnosis.

Variation in the prevalence, awareness, and control of diabetes in a multiethnic population: a nationwide population study in Malaysia.

The purpose of this study was to determine the association between different ethnic groups and the prevalence, awareness, and control of diabetes in Malaysia. A population-based cross-sectional study using multistage sampling was conducted in Malaysia. Diabetes is defined as having a fasting blood glucose > or =7 mmol/L or a self-reported diabetic on treatment.

Electrocardiographic markers of structural heart disease and predictors of death in 2332 unselected patients undergoing outpatient Holter recording.

Aims: To test the hypothesis that the QS interval of ventricular ectopic beats (VEBs) (ventricular ectopic QS interval, VEQSI) would provide a marker for the presence of structural heart disease and a predictor of mortality.

Methods And Results: We interviewed and examined 2332 patients undergoing Holter ECG monitoring for clinical indications. In persons with VEBs, the morphologies were counted and the QS interval was measured for each of these morphologies.

Potential demographic and baselines variables for risk stratification of high-risk post-myocardial infarction patients in the era of implantable cardioverter-defibrillator--a prognostic indicator.

Background: Risk stratification after myocardial infarction (MI) remains expensive and disappointing. We designed a prognostic indicator using demographic information to select patients at risk of dying after MI.

Method And Results: We combined individual patient data from the placebo arms of EMIAT, CAMIAT, TRACE and DIAMOND-MI with LVEF View Article and Find Full Text PDF

Arrhythmic complications of electrical cardioversion: relationship to shock energy.

Background: Existing guidelines for electrical cardioversion (ECV) of atrial arrhythmias suggest starting at a low energy setting on the grounds that shocks of high energy might damage the myocardium or trigger more serious arrhythmias. We hypothesised that more powerful shocks would exceed the upper limit of vulnerability for inducing ventricular fibrillation. The initial use of higher energy could therefore reduce arrhythmic complications.

Optimising the dichotomy limit for left ventricular ejection fraction in selecting patients for defibrillator therapy after myocardial infarction.

Background: The selection of patients for prophylactic implantable cardioverter-defibrilator (ICD) treatment after myocardial infarction (MI) remains controversial.

Aim: To determine the optimum left ventricular ejection fraction (LVEF) dichotomy limit for ICD treatment in patients with a history of MI.

Methods And Results: Data from the placebo arms of four randomised trials were pooled to create a cohort of 2828 patients (2206 men, mean (SD) age 65 (11) years) with reduced left ventricular function after MI.

Prognostic value of blood pressure measured during hospitalization after acute myocardial infarction: an insight from survival trials.

Background: The prognostic value of blood pressure measured during hospitalization after acute myocardial infarction (MI) has not been investigated, particularly with regard to arrhythmic death.

Methods: A total of 3311 placebo patients (2612 men, median age 64 years; range 23-92) from the EMIAT, CAMIAT, SWORD, TRACE and DIAMOND-MI studies with left ventricular ejection fraction less than 40% or asymptomatic ventricular arrhythmia surviving more than 45 days after MI were pooled. Systolic and diastolic blood pressures and pulse pressures were measured soon after MI (median 6 days, range 0-53 days).

Distribution and prognostic significance of QT intervals in the lowest half centile in 12,012 apparently healthy persons.

The presence of an abnormally short QT interval has been noted among survivors of idiopathic ventricular fibrillation and among close relatives of victims of unexplained sudden death. Most reported cases have had rate-corrected QT (QTc) intervals of <300 ms. The prevalence of such values in the community has not been documented.

Prognostic impact of demographic factors and clinical features on the mode of death in high-risk patients after myocardial infarction--a combined analysis from multicenter trials.

Background: Contemporary information is lacking on the effect of demographic features and clinical features on the specific mode of mortality after myocardial infarction (MI) in the thrombolytic era.

Hypothesis: The aims of this study were (1) to examine the risk and trend of a different mode of mortality (i.e.

Temporal trends on the risk of arrhythmic vs. non-arrhythmic deaths in high-risk patients after myocardial infarction: a combined analysis from multicentre trials.

Aims: An understanding of the temporal trends on the risks of arrhythmic death (AD) vs. non-arrhythmic deaths (NAD) after myocardial infarction (MI) is crucial in deciding the optimal timing for risk stratification and treatment window for prophylactic antiarrhythmic treatment. However, contemporary data on such information is lacking.

Potential cardiac toxicity of H1-antihistamines.

Nonsedating H1-antihistamines are widely prescribed for the treatment of allergic disorders because of their lack of sedative and anticholinergic effects; however, certain nonsedating antihistamines such as terfenadine and astemizole are now known to cause QT prolongation and TdP, particularly in overdosage or with concomitant ingestion of imidazole antifungals or macrolide antibiotics. Mechanistic studies showed that the cardiotoxic effects of some nonsedating antihistamines are due to the inhibition of repolarization potassium channels, particularly IKr, which leads to prolongation of the action potential and QT interval, and the development of early after-depolarization, which triggers TdP. Patients at risk of developing TdP, such as those with congenital long QT syndrome, cardiac disease, liver disease, electrolyte disturbance, or those taking drugs that can prolong QT interval, should avoid nonsedating antihistamines that are also capable of prolonging the QT interval.