Clinical significance of ventricular premature beats in an outpatient population

Diagnostic and prognostic significance of premature ventricular complexes in community and hospital-based participants: A scoping review

Background

While there are published studies that have examined premature ventricular complexes (PVCs) among patients with and without cardiac disease, there has not been a comprehensive review of the literature examining the diagnostic and prognostic significance of PVCs. This could help guide both community and hospital-based research and clinical practice.

Methods

Scoping review frameworks by Arksey and O’Malley and the Joanna Briggs Institute (JBI) were used. A systematic search of the literature using four databases (CINAHL, Embase, PubMed, and Web of Science) was conducted. The review was prepared adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Review (PRISMA-ScR).

Results

A total of 71 relevant articles were identified, 66 (93%) were observational, and five (7%) were secondary analyses from randomized clinical trials. Three studies (4%) examined the diagnostic importance of PVC origin (left/right ventricle) and QRS morphology in the diagnosis of acute myocardial ischemia (MI). The majority of the studies examined prognostic outcomes including left ventricular dysfunction, heart failure, arrhythmias, ischemic heart diseases, and mortality by PVCs frequency, burden, and QRS morphology.

Conclusions

Very few studies have evaluated the diagnostic significance of PVCs and all are decades old. No hospital setting only studies were identified. Community-based longitudinal studies, which make up most of the literature, show that PVCs are associated with structural and coronary heart disease, lethal arrhythmias, atrial fibrillation, stroke, all-cause and cardiac mortality. However, a causal association between PVCs and these outcomes cannot be established due to the purely observational study designs employed.

High burden of premature ventricular contractions in structurally normal hearts: To worry or not in pediatric patients?

BACKGROUND

There is paucity of data regarding the significance of high percentage of premature ventricular contractions (PVCs) in healthy children and their impact on left ventricular (LV) function and the risk of ventricular arrhythmias. The purpose of this study was to assess the prevalence of LV systolic dysfunction in children with frequent PVCs and determine whether PVC characteristics were predictive of LV dysfunction.

METHODS

We performed a single-center retrospective review to examine the prevalence of PVC-induced cardiomyopathy and natural history of PVC burden in children with frequent PVCs. Children aged 6 months-21 years with PVCs noted on 24-hr Holter monitoring studies were enrolled. The four categories included those with a PVC burden of >10%, 10%-20%, and those with more than 20% PVC burden.

RESULTS

A total of 134 children were included, 65 with more than 10% PVCs and 31 with more than 20% PVCs. Median age of the patients was 10.5 years (IQR 6.1-14.8 years), with 79 males (54.5%). Median PVC burden was 8.7% (IQR 4.2%-16.9%) with median follow-up of 2.8 years (IQR 1.2-4.6 years). During 2.8 years (1.3-4.3 years) of follow-up, the PVC burden decreased by 67% of baseline PVC burden in those who did not undergo any intervention. There were no deaths.

CONCLUSION

PVCs in children with structurally normal hearts are associated with a relatively benign course, with trend toward spontaneous resolution.

Ventricular Arrhythmias in the Patient with a Structurally Normal Heart

Ventricular arrhythmias (VAs) are among the most common cardiac rhythm disturbances encountered in clinical practice. Patients presenting with frequent ventricular ectopy or sustained ventricular tachycardia represent a challenging and worrisome clinical scenario for many practitioners because of concerning symptoms, frequent associated acute hemodynamic compromise, and the adverse prognostic implications inherent to these cases. While an underlying structural or functional cardiac abnormality, metabolic derangement, or medication toxicity is often readily apparent, many patients have no obvious underlying condition, despite a comprehensive diagnostic evaluation. Such patients are diagnosed as having an idiopathic VA, which is a label with specific implications regarding arrhythmia origin, prognosis, and potential for pharmacologic and invasive management. Further, a subset of patients with otherwise benign idiopathic ventricular ectopy can present with polymorphic ventricular tachycardia and ventricular fibrillation, adding a layer of complexity to a clinical syndrome previously felt to have a benign clinical course. Thus, this review seeks to highlight the most common types of idiopathic VAs with a focus on their prognostic implications, underlying electrophysiologic mechanisms, unique electrocardiographic signatures, and considerations for invasive electrophysiologic study and catheter ablation. We further address some of the data regarding idiopathic ventricular fibrillation with respect to the heterogeneous nature of this diagnosis.

The relaxation response: history, physiological basis and clinical usefulness

Considerable emphasis has been placed upon the relation of behavioural factors to the development of coronary artery disease. There is, however, the opposite potential: behavioural processes may lead to the alleviation and reversal of some of the predisposing features of this illness. This paper presents evidence that specific behaviours and thought patterns are associated with the elicitation of an innate physiological capacity termed the relaxation response. It will discuss the history of this response, its physiological basis, clinical usefulness (particularly in prevention) and some recent findings concerning the underlying mechanism of its actions.

The predictive value of resting electrocardiograms for 12-year incidence of coronary heart disease in the Honolulu Heart Program

The predictive value of electrocardiographic (ECG) abnormalities at baseline for subsequent risk of fatal and total coronary heart disease (CHD) was analyzed in a 12-year follow-up of 7682 men in the Honolulu Heart Program aged 45-68 who were free of CHD at baseline. Univariate analysis showed that men with major or minor ECG abnormalities, ST depression, high R wave, T-wave inversion, left ventricular hypertrophy or strain and premature ventricular contractions had considerably higher (2-10 fold) CHD incidence rates than those with normal ECG. When blood pressure, cigarette smoking, body mass index, alcohol use, physical activity, serum glucose, serum cholesterol, serum uric acid, age and years lived in Japan were taken into consideration through multivariate analysis, the ECG abnormalities retained significant associations with fatal and total CHD. This study demonstrated that resting ECG abnormalities were independent predictors of both total and fatal CHD.

Prognosis of ventricular arrhythmias in relation to sudden cardiac death: therapeutic implications

The hypothesis that ventricular arrhythmias represent an independent predictor of sudden cardiac death was examined by analyzing the published data. The frequency and complexity of ventricular arrhythmias increase progressively both with age and severity of heart disease, but no age- or disease-related norms have been established for clinical guidance. Simple and complex arrhythmias, including short runs of ventricular tachycardia, do not increase risk of sudden cardiac death in subjects without heart disease or with heart disease and normal myocardial function. Progression of nonsustained into sustained ventricular tachycardia in such individuals is rare. Simple and complex ventricular arrhythmias are not strong independent predictors of sudden death in survivors of myocardial infarction. In these, the overall incidence of sudden cardiac death averages 3.5 to 5% during the first year, but is about 15 to 20% per year in patients with severely impaired ventricular function. The results of this survey suggest that in patients with well preserved ventricular function, prophylactic use of antiarrhythmic drugs is not indicated, and that treatment of asymptomatic or mildly symptomatic ventricular arrhythmias is not likely to reduce the incidence of sudden cardiac death.

Correlates of cardiac and sudden death after ambulatory monitoring in a community hospital. Importance of clinical characteristics, congestive heart failure and tachyarrhythmias

To analyze the prognostic importance of arrhythmias on routine 24-hour ambulatory monitoring, we prospectively followed 755 consecutive patients undergoing monitoring at a community hospital in the context of usual medical care. Of the 755 patients, 114 (15%) had ventricular tachycardia on monitoring. At a mean follow-up of 38 months, multivariate survival analysis indicated that congestive heart failure was the strongest correlate of death from all causes (relative risk (RR) = 2.6), cardiac death (RR = 3.5), and the sudden cardiac death (RR = 5.6); ventricular tachycardia was significantly correlated with death from all causes and with cardiac death, but had only a borderline association with sudden cardiac death (RR = 1.9, p = 0.08). While ventricular tachycardia on ambulatory monitoring is of prognostic importance, congestive heart failure, as determined by routine clinical examination, was a more powerful prognostic correlate of deaths from all causes, death from cardiac causes, and sudden cardiac death.

Electrophysiologic testing in patients with recurrent syncope: are results predicted by prior ambulatory monitoring?

Syncope is a common medical problem which can result from many etiologies, including cardiac dysrhythmias. Because ambulatory monitoring usually fails to capture a syncopal episode, electrophysiologic testing has been used to elucidate dysrhythmic mechanisms in patients with recurrent syncope. To assess whether findings on ambulatory monitoring not obtained during syncope can be used to indicate the results which are found on electrophysiologic testing in patients with recurrent syncope, we reviewed the ambulatory monitoring records of 59 such patients referred for electrophysiologic testing. Although 29 patients had abnormalities on electrophysiologic testing, 13 of which were severe, in only six were the findings suggested by the abnormalities recorded during ambulatory monitoring. Twenty-one patients actually had concordance between electrophysiologic testing and ambulatory monitoring results, but in 15 of the 21 results of both tests were normal. Severe abnormalities were more frequently detected in our patient population by electrophysiologic testing than by ambulatory monitoring, especially if patients had organic heart disease.

Complex arrhythmias in mitral regurgitation with and without mitral valve prolapse: contrast to arrhythmias in mitral valve prolapse without mitral regurgitation

Atrial and ventricular arrhythmias were characterized by ambulatory electrocardiography in 31 patients with nonischemic mitral regurgitation (MR), 17 of whom had echocardiographic evidence of mitral valve prolapse (MVP) and 14 of whom had other causes of MR. Frequent and complex arrhythmias were common and equally prevalent in each MR subgroup, whether or not MVP was present. Multiform ventricular ectopy was found in 77% (24 of 31), ventricular couplets in 61% (19 of 31), and ventricular salvos or ventricular tachycardia in 35% (11 of 31) of patients with MR. Arrhythmias in patients with MR were significantly more prevalent than in 63 patients with MVP who had no evidence of MR. Among patients with MVP, excess arrhythmias associated with MR were most striking with respect to frequent ventricular premature complexes (41% with MR vs 3% without MR), multiform ventricular ectopic activity (88% vs 43%), ventricular couplets (65% vs 6%), and ventricular salvos or ventricular tachycardia (35% vs 5%) (p less than 0.005 for each comparison). These data demonstrate that complex arrhythmias are common in patients with nonischemic MR irrespective of etiology, and that these arrhythmias are more strongly associated with hemodynamically important MR than with MVP alone.

New approaches to drug selection and serial drug testing

Sudden cardiac death is a major problem in the United States. Our goal is to identify high-risk patients and to be able to target antiarrhythmic therapy to this population. Ambulatory electrocardiography, exercise tolerance testing, and programmed electrical stimulation studies may aid in the identification of patients at risk for sudden cardiac death and the selection of antiarrhythmic therapy. Each technique has its advantages, disadvantages, and limitations. These considerations must be taken into account if the procedure is to be optimally employed. We are in a period of rapid development of new antiarrhythmic agents. It is essential to fully understand the techniques employed to evaluate antiarrhythmic therapy.

Relation of ventricular premature beats to underlying heart disease

The relation between ventricular premature beats (VPBs) and physiologic disease was investigated in 305 patients who had 24-hour Holter monitoring tests, cardiac catheterization and angiography. Both frequency and Lown class of VPBs were measured. Analyses showed that occurrence of VPBs at an average frequency of more than 2 per hour or occurrence of complex VPBs (Lown class greater than 2) have the highest association with the presence and severity of cardiac disease. Using these criteria, VPB severity was then compared with extent of ventricular wall motion abnormality (right anterior oblique projection segments), ejection fraction, end-diastolic pressure, category of disease (normal, coronary artery disease [CAD], valvular heart disease, dilated cardiomyopathy), age and severity of CAD (major coronary arteries with greater than 75% diameter reduction). Severe VPBs defined either by complexity or frequency were significantly correlated with extent of wall motion abnormality, ejection fraction, category of disease and age. Severe VPBs were not significantly correlated with end-diastolic pressure or severity of CAD. Discriminant analysis then showed that in addition to wall motion abnormality and ejection fraction, category of disease and age are independently correlated with VPB severity.

Q waves and ventricular extrasystoles in resting electrocardiograms. A 16 year follow up in Busselton study

Isolated abnormalitites in the resting electrocardiograms of 1546 Busselton people with no history of angina or past myocardial infarction were examined in relation to 16 year mortality. Multivariate discriminate analysis in men showed significant independent relationship for Q waves with coronary heart disease and for ventricular extrasystoles with cardiovascular disease. In women multivariate analysis showed significant relations for ventricular extrasystoles with total mortality and coronary heart disease. There were higher trends in mortality for both men and women with frequent ventricular extrasystoles compared with those with infrequent ventricular extrasystoles.

Relationship of ventricular ectopy in men without apparent heart disease to occurrence of ischemic heart disease and sudden death

The purpose of this investigation was to determine whether ventricular ectopic beats, or ventricular premature beats (VPBs), on routine electrocardiograms in men without apparent heart disease predict the later occurrence of clinical manifestations of ischemic heart disease (IHD). The Manitoba Study cohort consisted of 3983 men predominantly between 25 and 34 years of age and free of IHD at entry. During the 29-year observation period, 401 persons without clinical evidence of heart disease had VPBs on an electrocardiogram at a routine examination. They were followed 10.8 +/- 0.5 (SEM) years and 13.5% (54 men) later manifested IHD. Age-specific total IHD incidence was significantly (p less than 0.05) greater for men 40 to 59 years of age at VPB occurrence compared to men of the same age without VPBs. The clinical manifestation with the strongest association with VPBs was sudden death. VPB characteristics of frequency, configuration, coupling interval, and postextrasystolic T-wave change did not distinguish those who developed IHD. Prematurity index (R-R'/QT) showed a trend toward an association of late coupled ectopic beats (R-R'/QT greater than 1.6) and IHD risk. However, faster basic ventricular rate plus VPBs significantly correlated with greater IHD probability. Thus ventricular ectopic beats on a routine electrocardiogram in men over 40 years of age without apparent heart disease identify those at high risk for a clinical IHD event, especially sudden death.

Repolarization abnormalities in survivors of out-of-hospital ventricular fibrillation

Survivors of out-of-hospital ventricular fibrillation (VF) are at high risk for recurrent VF, probably reflecting continued myocardial electrical instability. In this study 12-lead ECGs of 125 VF survivors with coronary heart disease were examined and compared to those of 98 ambulatory post-MI patients. The study was part of an effort to define clinical identifiers of patients likely to develop sudden cardiac death. Ventricular fibrillation survivors were commonly had premature ventricular complexes (PVCs):30% versus 13% (P less than 0.01). In addition, ECGs of VF survivors showed a significantly greater prevalence of ST-segment depression (46% versus 10%), T wave flattening (52% versus 26%), and QTc prolongation (35% versus 18%). It is proposed that these repolarization abnormalities represent asynchronous repolarization, which together with frequent PVCs, may set the stage for re-entrant ventricular dysrhythmias and ultimately VF. It is also possible that repolarization abnormalities together with premature ventricular contractions might serve as markers of patients with coronary heart disease who are at increased risk for sudden cardiac death.

Premature ventricular contractions in normal children

To document the assumed benign prognosis of premature ventricular contractions in children, we followed 17 patients with PVCs and without other heart disease for a mean of seven years (range one to 19 years). Data were collected from the history, physical examination, 15-lead ECG, and treadmill exercise test. Eight of the 17 children still had PVCs at the most recent follow-up. Of these eight children, seven were asymptomatic. The physical examination remained normal in all except one, who developed signs of mitral prolapse. Light exercise abolished the PVCs in all children. We believe that if a careful clinical examination discloses no abnormalities, and if the PVCs are unifocal and disappear with exercise, this dysrhythmia is, in fact, benign in children, and requires no further cardiovascular examination.

Identification of sudden death risk factors in acute and chronic coronary artery disease

Because of their potential role in the pathogenesis of sudden death, cardiac arrhythmias in patients with coronary artery disease have become the subject of increasing concern and investigation. A series of studies on the problem of ventricular ectopy as it relates to the entire spectrum of sudden death in coronary disease were carried out utilizing continuous portable electrocardiographic monitoring systems. Evaluation of arrthymias during the entire 3 week in-hospital period after acute myocardial infarction in 83 patients revealed that absence of premature ventricular contractions, including their serious forms (multifocal, paired, R on T phenomenon, frequency 5/min or greater) and ventricular tachycardia in the coronary care unit did not exclude their high incidence rate (premature ventricular contractions 30 percent, serious forms 41 percent, ventricular tachycardia 6 percent) in the late hospital phase. Because late hospital serious forms of ventricular ectopy correlated with arterial hypoxia and elevated left ventricular filling pressure in the coronary care unit and with persistent S-T abnormalities, the extent of left ventricular dysfunction and ischemia with acute myocardial infarction appeared precursors to these arrhythmias. Study of ventricular ectopy in the late hospital phase of acute myocardial infarction indicated that ventricular ectopy and particularly its serious forms and prognostic significance relative to subsequent sudden death after discharge; the extent of predischarge S-T segment alterations was greater in subjects who died suddenly than in survivors, suggesting that persistent ischemia or segmental dyssynergy, or both, predisposed to lethal arrhythmias. Among 86 patients with chronic coronary disease documented by catheterizerization, 87 percent had ventricular ectopy and 62 percent serious ventricular arrhythmias, in contrast to 34 percent and 9 percent, respectively in normal subjects; frequency of serious forms of ventricular ectopy was related to extent of coronary atherosclerosis. Correlation of standard electrocardiograms with continuous Holter electrocardiograms in 101 patients with chronic coronary disease over 24 months revealed that the former modality was insensitive in arrhythmia detection; patients free of ventricular ectopy by serial standard electrocardiograms had a 62 percent incidence rate of serious forms of ventricular ectopy and 6 percent ventricular tachycardia on portable continuous monitoring. Additional studies of patients with chronic coronary disease showed that assessment of both the type of ventricular ectopy and the setting in which it occurs provides the most meaningful characterization of risk of sudden death. These systematic series of observations identify premature ventricular ectopic beats as important and separate risk factors in coronary disease...

Vectorial characteristics of ventricular extrasystoles stimulated during cardiac catheterization

Ventricular extrasystoles (VES) from different areas of the ventricular muscle mass were obtained by mechanical stimulation of inflow and outflow regions of the right ventricle (RV) and apical and basal portions of the left ventricle (LV) during cardiac catheterization. Cube system vectorcardiogram (VCG) patterns of VES from each location were analyzed to determine the specificity of vector orientation from each site. Transverse plane VCG distinguished between nonseptal LVES and RVES, while a combination of transverse and either sagittal or frontal planes permitted further localization of septal VES to inflow or outflow regions of the RV and apical and basal areas of the LV.

Decreased premature ventricular contractions through use of the relaxation response in patients with stable ischaemic heart-disease

To determine whether decreased sympathetic-nervous-system activity achieved by the relaxation response could decrease premature ventricular contractions (P.V.C.s), eleven ambulatory patients with proven, stable ischaemic heart-disease and P.V.C.s were investigated. The patients, who were taking no medication for the P.V.C.s, were trained to elicit regularly the relaxation response through a non-cultic psychological technique. The frequency of the P.V.C.s was measured by computer analysis of Holter monitor tapes for 2 complete days before learning the technique, which was learned in approximately 5 minutes after the second day. Patients were instructed to evoke the response for 20 minutes twice daily thereafter. After 4 weeks, a reduced frequency of P.V.C.s was documented in eight of the eleven patients. This effect was especially striking during the sleeping hours and less so during the entire monitoring session. The relaxation response is a simple, no cost, non-pharmacological mechanism without side-effects which seemed to decrease the frequency of P.C.V.s in most patients with ischaemic heart-disease.

Relation of ventricular arrhythmias in the late hospital phase of acute myocardial infarction to sudden death after hospital discharge

To determine the prognostic significance of ventricular arrhythmias persisting during the hospital ambulatory phase of acute myocardial infarction, 64 patients with acute myocardial infarction underwent continuous 10-hour Holter monitoring an average of 11 days after discharge from the coronary care unit (CCU). Patients were categorized according to the results of ambulatory monitoring: 27 patients had ventricular extrasystoles, which were complicated (multifocal, R on T, paired, more than 5/min), or ventricular tachycardia; 22 had uncomplicated premature ventricular contractions; and 15 exhibited no ventricular arrhythmias. The 64 patients were followed prospectively for an average course of 25.8 months; 12 died suddenly; 8 died of other causes, and 44 survived. In all patients who died suddenly, ventricular ectopy was recorded on Holter monitoring before their discharge from the hospital (complicated premature ventricular contractions, eight patients; uncomplicated premature ventricular contractions, four patients); there were no sudden deaths in the patients without ventricular arrhythmias. Patients who died suddenly and those survived were similar in respect to age (60, 62 years), sex, location of infarction, presence of coronary risk factors, severity of acute myocardial infarction (Q waves, cardiac enzymes), serum cholesterol levels, evidence of cardiomegaly on roentgenograms, presence of ventricular gallop and drug therapy received. The occurrence of acute arrhythmias in the CCU did not separate patients who died suddenly from those who survived; there were no differences in ventricular tachycardia or ventricular fibrillation (3 or 12 patients who died suddenly, 6 of 44 patients who survived) or complicated premature ventricular contractions (4 or 12 patients who died suddenly, 18 of 44 patients who survived). Electrocardiograms obtained late in the hospital course revealed no differences in the extent of Q or T wave changes between these two groups. However, the extent of S-T segment abnormality was greater in patients who died suddenly than in patients who survived (5.6 compared to 1.8 leads/standard tracing, p smaller than 0.02) suggesting that the arrhythmias in the former were related to persistent ischemia or segmental ventricular dyssynergy. Thus, in this relatively small number of patients, ventricular arrhythmias persisting late in the hospital course of patients admitted for acute myocardial infarction are shown to predispose to subsequent sudden death.