QRS Prolongation In Patients Research Articles

Effects of dapagliflozin according to QRS duration across the spectrum of LVEF: An analysis of DAPA-HF and DELIVER

Abstract Aims To document the prevalence of QRS prolongation in patients with HFrEF and HFmrEF/HFpEF, the association between QRS duration and outcomes, and the effect of dapagliflozin according to QRS duration across the spectrum of LVEF. Methods A pooled analysis of the DAPA-HF and DELIVER trials, excluding patients with a paced rhythm and CRT was conducted. The information collected was used to categorize patients according to QRS duration based on the cutpoints used in the CRT trials, as follows: QRS <120 ms, QRS 120-149 ms, and QRS ≥ 150 ms. The data were analyzed according to these categories and using QRS duration as a continuous variable. Results Overall, 4004 patients had HFrEF, and 5820 had HFmrEF/HFpEF. QRS duration (ms) was <120 in 7039 patients (71.7%), 120–149 in 1725 (17.6%), and ≥150 in 1060 patients (10.8%). The median follow-up time was 23 months. The rate of the primary composite outcome of CV death or worsening HF was 9.2 (95%CI 8.7-9.7), 14.3 (13.0-15.7), and 15.9 (14.1-17.9) per100 patient-years in the <120, 120–149, and ≥150 ms groups, respectively. This gradient in event rates was observed both in HFrEF and HFmrEF/HFpEF. Dapagliflozin, compared with placebo, reduced the risk of the primary outcome, consistently, across the QRS duration subgroups: hazard ratio (95% CI) 0.75 (0.67-0.85), 0.79 (0.65-0.96) and 0.89 (0.70-1.13) in the <120, 120–149, and ≥150 ms groups, respectively (P for interaction 0.28). The effect of dapagliflozin on the primary outcome was consistent across the QRS duration regardless of HF phenotype i.e., HFrEF or HFmrEF/HFpEF. Conclusion Prolongation of QRS duration is associated with worse outcomes irrespective of HF phenotype. Dapagliflozin reduced the risk of the primary outcome, regardless of QRS duration, in DAPA-HF and DELIVER.KM curves according to QRS durationEffect of dapagliflozin on outcomes

Implications of QRS Prolongation in Patients With Atrial Fibrillation (from a Multicenter Outpatient Registry)

Patients with atrial fibrillation (AF) at the highest risk of progression to heart failure (HF) need to be identified. We investigated whether QRS duration can stratify patients with AF at risk for poor clinical outcomes, including health-related quality of life (HR-QoL). We analyzed data from a multicenter registry-based cohort study of patients with AF. Patients were grouped according to the QRS duration (narrow: <120 ms; wide: ≥120 ms) at registration (baseline). The primary outcome was a composite of all-cause death and HF hospitalizations during a 2-year follow-up. In addition, the AF effect on the quality-of-life overall summary score was compared between the groups. In 3,269 patients, 302 (9.2%) had a wide QRS; these patients were more likely to be older, male, and have higher CHA₂DS₂-VASc scores than those with a narrow QRS. The incidence of the composite outcome was higher in patients with a wide QRS than those with a narrow QRS (13.1% vs 4.9%, p <0.001). After adjustment, a wide QRS was an independent predictor of the primary outcome (adjusted hazard ratio 1.58, 95% confidence interval 1.09 to 2.29, p=0.016), and the results persisted after the exclusion of patients with bundle branch block or cardiac implantable electronic devices. Regarding HR-QoL outcomes, patients with a wide QRS were less likely to improve AF effect on quality-of-life overall summary scores at 1 year than those with a narrow QRS (adjusted difference -2.31, 95% confidence interval -4.06 to -0.57, p=0.009). QRS prolongation, even for a nonspecific conduction disturbance, was an independent predictor of adverse outcomes and worse HR-QoL in patients with AF.

Effect of heart rate on the intrinsic and the ventricular-paced QRS duration

BackgroundWe evaluated the effect of heart rate on the intrinsic and the ventricular-paced QRS duration in implanted device recipients with normal or reduced left ventricular ejection fraction (EF). MethodsWe studied 239 outpatients with preserved intrinsic ventricular activation and normal (n=92) or reduced (n=147) EF who had apical (RVA) or mid-septal (RVS) right ventricular lead position. The QRS duration was measured at baseline and during atrial-based pacing at increased heart rate to ensure intrinsic or ventricular-paced QRS activation. ResultsThe heart rate increase shortened the intrinsic QRS only in patients with normal EF, and further prolonged the ventricular-paced QRS in patients with reduced EF and either narrow or wide QRS (p<0.001), irrespective of RVA or RVS pacing (p<0.01). ConclusionHeart rate increase is associated with further QRS prolongation in patients with reduced EF, regardless of RVA or RVS pacing site.

Ventricular conduction and long-term heart failure outcomes and mortality in African Americans: insights from the Jackson Heart Study.

QRS prolongation is associated with adverse outcomes in mostly white populations, but its clinical significance is not well established for other groups. We investigated the association between QRS duration and mortality in African Americans. We analyzed data from 5146 African Americans in the Jackson Heart Study stratified by QRS duration on baseline 12-lead ECG. We defined QRS prolongation as QRS≥100 ms. We assessed the association between QRS duration and all-cause mortality using Cox proportional hazards models and reported the cumulative incidence of heart failure hospitalization. We identified factors associated with the development of QRS prolongation in patients with normal baseline QRS. At baseline, 30% (n=1528) of participants had QRS prolongation. The cumulative incidences of mortality and heart failure hospitalization were greater with versus without baseline QRS prolongation: 12.6% (95% confidence interval [CI], 11.0-14.4) versus 7.1% (95% CI, 6.3-8.0) and 8.2% (95% CI, 6.9-9.7) versus 4.4% (95% CI, 3.7-5.1), respectively. After risk adjustment, QRS prolongation was associated with increased mortality (hazard ratio, 1.27; 95% CI, 1.03-1.56; P=0.02). There was a linear relationship between QRS duration and mortality (hazard ratio per 10 ms increase, 1.06; 95% CI, 1.01-1.12). Older age, male sex, prior myocardial infarction, lower ejection fraction, left ventricular hypertrophy, and left ventricular dilatation were associated with the development of QRS prolongation. QRS prolongation in African Americans was associated with increased mortality and heart failure hospitalization. Factors associated with developing QRS prolongation included age, male sex, prior myocardial infarction, and left ventricular structural abnormalities.

One of the causes of secondary cardiyomyopathies: Diabetic cardiomyopathy

We read with great interest the article entitled “The clinical correlates and prognostic impact of QRS prolongation in patients with dilated cardiomyopathy: A single-center cohort study” by Xiaoping Li et al. [ [1] Li X. Luo R. Chan C.P. et al. The clinical correlates and prognostic impact of QRS prolongation in patients with dilated cardiomyopathy: a single-center cohort study. Int J Cardiol. 2014; 172: 475-557 Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar ]. They observed that the prolongation of the QRS duration at admission is a predictor of mortality in patients with dilated cardiomyopathy. In their study, the patients with QRS ≥ 120 ms had a higher all-cause mortality rate than those with QRS < 120 ms and that QRS duration was a strong predictor of all-cause mortality in patients with DCM even after adjustment for the classic risk factors.

The clinical correlates and prognostic impact of QRS prolongation in patients with dilated cardiomyopathy: A single-center cohort study

a Cardiac Arrhythmia Center, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100037, China b Department of Cardiology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072, China c The Center of Heart Development, Key Lab of MOE for Development Biology and Protein Chemistry, College of Life Science, Hunan Normal University, Changsha, Hunan 410081, China d Division of Cardiology, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong

Prognostic value of the Intermediate QRS prolongation in patients with acute myocardial infarction.

Studies have shown different effect of intermediate QRS prolongation on major cardiovascular events in acute myocardial infarction (AMI) patients. The aim of this study was to investigate the predictive and prognostic value of intermediate QRS prolongation on in-hospital complication rate and long term mortality in patients with AMI. We performed an observational study that enrolled 114 consecutive patients with AMI. Patient's admission electrocardiography (ECG) were enlarged two fold, and QRS duration (QRSd) was measured manually. Patients were divided into two groups according to the admission EKG QRSd. Group A defined as patient with QRSd between 90-120 msn and group B QRSd <90msn. Echocardiographic, angiographic, clinic and laboratory results were recorded for all patients. Patients were followed next twelve months. In-hospital follow-up period, major adverse cardiac events were higher in group A than group B (0.9 ±0.9 vs. 0.5 ±0.5 p=0.02). There were increased end-diastolic and end-systolic volume in group A (91±15 vs. 82±12 p=0.002; 50±10 vs. 44±9 p=0.002. respectively). Left ventricular ejection fraction (LVEF) was lower in group A. but it did not reach statistical significance (43.5±6.3 vs. 45.5±5.5 p=0.06). Angiographic evaluation was detected severe coronary artery disease (CAD) in group A than group B (1.9±0.8 vs. 1.5±0.7 p=0.013). During 12 months of follow-up period. five patients were died. Although these patients had longer QRSd on admission, it was not statistically significant (96±14 vs. 90±11 p=0.3). Intermediate QRS prolongation on admission EKG were found to be positively correlated with increased EDV, ESV, major in-hospital cardiovascular events, and multivessel coronary artery disease and inversely correlated with LVEF. Although deceased patients had prolonged QRSd it was not statistically significant.

GW24-e2922 The clinical correlates and prognostic impact of QRS prolongation in patients with dilated cardiomyopathy

ObjectivesProlongation of the QRS duration (≥ 120 ms) has been suggested to be an independent risk factor for mortality in patients with heart failure. The purpose of this study was...

Effects of HIV Protease Inhibitors on Cardiac Conduction Velocity in Unselected HIV-Infected Patients

We examined the prevalence and the extent of prolongation of the PR and QRS intervals and their relation to anti-HIV treatments and other clinical characteristics in 970 HIV-infected patients, 749 treated with antiretroviral therapy and 221 untreated. Age, body mass index, heart rate, and treatment with β-blockers and HIV protease inhibitors (PIs) were independent predictors of increase in the duration of the PR interval. Male gender, Caucasian ethnicity, heart rate, duration of antiretroviral therapy, and use of PIs were independent predictors of an increase in the duration of the QRS interval. Users of HIV PIs had an adjusted QRS-interval duration that was 2.6 ms (95% confidence interval (CI) 1.4-3.9) longer than the interval in nonusers (P = 0.0004). The adjusted odds ratios of first-degree atrioventricular block (n = 54) and complete bundle branch block (n = 23) were 1.62 (95% CI 0.90-2.89; P = 0.10) and 2.71 (95% CI 1.10-7.13; P = 0.03), respectively, in patients taking PIs. These findings may have important clinical implications, particularly with respect to QRS prolongation in patients with myocardial ischemia or heart failure.

QRS Prolongation in Patients with Acute Coronary Syndromes

This study used data from the Canadian Acute Coronary Syndromes (ACS) Registry to evaluate the relationship between QRS duration, with and without left or right bundle branch block (BBB), and 1-year mortality in ACS. In the study, 5003 patients were admitted to the hospital for ACS. The authors divided these patients into four groups: QRS<120 ms (n=4289), QRS>120 ms without BBB (n=202), left BBB (n=262), and right BBB (n=250) based on their initial electrocardiogram. These groups were evaluated for predictive value of in-hospital mortality and 1-year mortality.

QRS prolongation in patients with acute coronary syndromes

QRS prolongation with or without bundle branch block (BBB) has been associated with adverse outcome in myocardial infarction; we examined the relationship between QRS duration and outcome in a broad spectrum of patients with acute coronary syndrome (ACS). Core laboratory evaluation of the presenting electrocardiogram in Canadian ACS Registry patients (n = 5,003) showed 4,289 (85.7%) had QRS <120 milliseconds, 202 (4.0%) patients had QRS > or =120 milliseconds without BBB, 262 (5.2%) had left BBB (LBBB), and 250 (5.0%) had right BBB. Compared to patients with QRS <120 milliseconds, patients with QRS > or =120 milliseconds without BBB had higher in-hospital (3.5% vs 1.9%, odds ratio [OR] 1.87, 95% CI 0.85-4.09, P = .12) and 1-year mortality (14.9% vs 7.7%, OR 2.10, 95% CI 1.38-3.18, P = .001). In-hospital and 1-year mortality was significantly higher in patients with BBB (eg, LBBB compared with QRS <120 milliseconds) (5.0% vs 1.9%, OR 2.71, 95% CI 1.49-4.94, P = .001, and 23.8% vs 7.7%, OR 3.74, 95% CI 2.72-5.13, P < .001). Analyzed as a continuous variable and after adjustment for validated prognosticators, QRS duration was an independent predictor of 1-year death (OR 1.11, 95% CI 1.06-1.16, P < .001) and death/myocardial infarction (OR 1.06, 95% CI 1.02-1.11, P = .003). However, when using clinically applicable QRS duration evaluation, only LBBB was an independent predictor of 1-year mortality (OR 1.93, 95% CI 1.28-2.90, P = .002). In patients presenting with a broad spectrum of suspected ACS, QRS prolongation-particularly in the setting of LBBB-is an independent predictor of in-hospital and 1-year mortality.

Exercise-induced QRS prolongation in patients with mild coronary artery disease: Computer analysis of the digitized multilead ECGs

Although exercise-induced QRS prolongation has been reported as a possible marker for inducible ischemia, subtleness of the prolongation makes it unidentifiable from standard, chart-recorded electrocardiograms (ECGs). To overcome such a limitation, we measured the QRS width using high-resolution ECGs and examined the diagnostic value of the exercise-induced QRS prolongation in patients before and after percutaneous transluminal coronary angioplasty (PTCA). In 16 patients with single- (n = 12) or double-vessel disease (n = 4), treadmill exercise ECG tests were performed before and after PTCA, while continuously recording 8-lead ECGs at 500 Hz. The onset of the QRS complexes was defined by the earliest deflection, and the end was defined as the latest deflection among 8 leads with the use of algebraic sum of the absolute voltage and their time derivatives (dV/dt) from all 8 leads. We compared QRS complexes before and 1 minute after exercise. Before PTCA, exercise prolonged the QRS width in all but 3 patients (unchanged in 2, decreased in 1) (84 ± 7 to 87 ± 8 ms, P < .005). After PTCA, it decreased in 4, was unchanged in 5, and increased in 7 (83 ± 7 to 83 ± 6 ms, not significant). PTCA shortened postexercise QRS width in all but 3 (unchanged in 2, increased in 1: 83 ± 6 to 87 ± 8 ms, P < .001). High-resolution ECGs enabled us to measure subtle QRS prolongation induced by mild ischemia. Because the QRS prolongation and ST-segment changes would reflect different aspects of myocardial ischemia, incorporating this measure into ST segment criteria might significantly improve the diagnostic accuracy for coronary artery disease.

Relation between Exercise-Induced QRS Prolongation and Reversible Myocardial Perfusion Defects in Patients with Coronary Artery Disease

Acute myocardial ischemia decreases conduction velocity through the ischemic myocardium and may produce QRS prolongation on the surface electrocardiogram. To investigate the effect of exercise-induced myocardial ischemia on the QRS duration, 124 patients who underwent diagnostic cardiac catheterization and exercise thallium-201 scintigraphy were studied. Seventeen patients had normal coronary arteries and 107 had coronary artery disease. QRS duration decreased with exercise in patients with normal coronary arteries (-3.7 ms, confidence interval -7.7 to 0.3) but increased in patients with coronary artery disease; exercise-induced QRS prolongation was directly related to the number of vessel disease (1.2 ms in patients with one-vessel disease; 8.7 ms in patients with two-vessel disease, and 10.5 ms in patients with threevessel disease, p < 0.001). Likewise, exercise-induced QRS duration decreased in patients without exercise-induced reversible perfusion defects (-1.3 ms, confidence limits -2.8 to 0.2) but increased in patients with exercise-induced perfusion defects (9.7 ms in patients with one perfusion defect; 13.6 ms in patients with two perfusion defects, and 16.3 ms in patients with three perfusion defects, p < 0.001). Exercise-induced QRS prolongation was best related to the number of exercise-induced perfusion defects than to the number of vessel disease, p < 0.001. In conclusion, exercise-induced QRS prolongation in patients with coronary artery disease was directly related to the number of vessel disease and to exercise-induced perfusion defects. This QRS prolongation was better related to the number of reversible perfusion defects than to the number of vessel disease. Thus, exercise-induced QRS prolongation in patients with coronary artery disease may be a marker of exercise-induced myocardial ischemia.

Exercise-induced QRS prolongation in patients with hypertrophic cardiomyopathy

Exercise-induced QRS prolongation in patients with hypertrophic cardiomyopathy

Exercise-induced QRS prolongation in patients with coronary artery disease: A marker of myocardial ischemia

The objective of this study was to investigate the effect of myocardial ischemia on the QRS duration in patients with coronary artery disease since acute myocardial ischemia decreases conduction velocity through the ischemic myocardium and may produce QRS prolongation on the surface electrocardiogram. One hundred fifty patients who underwent cardiac catheterization and exercise radionuclide ventriculography within 1 month of each other were studied. Forty patients had normal coronary arteries and 110 had coronary artery disease. QRS duration decreased with exercise in patients with normal coronary arteries (−3.0 msec, confidence limits −6.2 to 0.2), but increased in patients with coronary artery disease; exercise-induced QRS prolongation was directly related to the number of diseased vessels (4.8 msec in patients with one, 7.8 msec in patients with two, and 13.3 msec in patients with three-vessel disease, p < 0.001). Likewise, QRS duration decreased with exercise in patients without exercise-induced segmental contraction abnormalities (−1.8 msec, confidence limits −3.7 to 0.1), but increased in patients with segmental contraction abnormalities (6.7 msec in patients with one, 13.5 msec in patients with two, and 21 msec in patients with three segmental contraction abnormalities, p < 0.0001). Exercise-induced QRS prolongation was better related to the number of segmental contraction abnormalities than to the number of diseased vessels ( p < 0.01). It was concluded that exercise produces QRS prolongation in patients with coronary artery disease in direct relation to the number of diseased vessels and to exercise-induced segmental contraction abnormalities. This QRS prolongation was more closely related to the number of exercise-induced segmental contraction abnormalities than to the number of diseased vessels. Thus exercise-induced QRS prolongation in patients with coronary artery disease may be a marker of exercise-induced myocardial ischemia.

Concentration-effect relations of 5-hydroxypropafenone in normal subjects

To evaluate the pharmacologic activity of 5-hydroxypropafenone, electrocardiographic changes (PQ and QRS duration) and blood pressure levels were measured in 6 healthy extensive metabolizers of debrisoquine after a single oral dose of 300 mg of this metabolite as a solution in a placebo-controlled, double-blind crossover study. Well-absorbed, with a lag time of 4.4 to 9.8 minutes, 5-hydroxypropafenone reached peak concentrations of 153 to 337 ng/ml after 20 to 51 minutes. The terminal half-life was 506 to 963 minutes. To describe the temporal aspects of the concentration-effect relation, a pharmacokinetic-pharmacodynamic model with a hypothetical effect compartment was applied. The relation between electrocardiographic changes and drug concentration at the effect site could be described by a linear regression model. Significant prolongations of PQ and QRS duration were found in 5 of 6 subjects. There were no changes in QTc interval, blood pressure measurements and heart rate in the supine position. However, blood pressure measurements in the upright position revealed a greater percent decrease of systolic blood pressure than with placebo (mean ± standard deviation −25.6 ± 13.8% vs −3.4 ± 13.1%, p < 0.05). It is concluded that 5-hydroxypropafenone exerts significant pharmacologic activity in humans as well as animals. Because QRS prolongation in patients treated with class IC antiarrhythmic drugs correlates with the antiarrhythmic effect, our data suggest that 5-hydroxypropafenone may contribute to the therapeutic activity of propafenone in humans.

QRS alterations immediately following production of left ventricular free-wall ischemia in dogs.

QRS alterations immediately following production of left ventricular free-wall ischemia in dogs.