Evaluation of left ventricular diastolic functions in patients with frequent premature ventricular contractions from right ventricular outflow tract

Arrhythmia-Induced Cardiomyopathy: JACC State-of-the-Art Review

Arrhythmias frequently accompany heart failure and left ventricular dysfunction. Tachycardias, atrial fibrillation, and premature ventricular contractions can induce a reversible form of dilated cardiomyopathy (CM) known as arrhythmia-induced CM (AiCM). The intriguing question is why certain individuals are more susceptible to AiCM, despite similar arrhythmia burdens. The primary challenge is determining the extent of arrhythmias' contribution to left ventricular systolic dysfunction. AiCM should be considered in patients with a mean heart rate of >100 beats/min, atrial fibrillation, or a PVC burden of >10%. Confirmation of AiCM occurs when CM reverses upon eliminating the responsible arrhythmia. Therapy choice depends on the specific arrhythmia, patient comorbidities, and preferences. After left ventricular function is restored, ongoing follow-up is essential if an abnormal myocardial substrate persists. Accurate diagnosis and treatment of AiCM have the potential to enhance patients' quality of life, improve clinical outcomes, and reduce hospital admissions and overall health care costs.

Risk of atrial fibrillation among patients with premature ventricular complexes: a systematic review and meta-analysis of cohort studies

INTRODUCTION

Atrial fibrillation (AF) is more likely found in patients with premature ventricular complexes (PVCs). Nonetheless, the outcomes of previous investigations remain inconclusive. To evaluate the link between PVCs and the risk of AF, we did a systematic review and meta-analysis.

EVIDENCE ACQUISITION

Potentially eligible studies were found by searching for published publications indexed in the MEDLINE and EMBASE databases from inception to April 13, 2021, looking for studies that assessed the risk of AF in patients with PVCs vs. those who did not have PVCs. Dersimonian and Laird's random-effect, generic inverse variance technique was used to calculate the pooled risk ratio (RR) and 95% confidence interval (CI).

EVIDENCE SYNTHESIS

The meta-analysis includes 6 cohort studies (1 prospective and 5 retrospective cohort studies) with a total of 9,662,088 individuals. We found that patients with PVCs have a significantly higher risk of AF than individuals without PVCs with the pooled RR of 1.90 (95% CI: 1.51-2.39, I²=83%).

CONCLUSIONS

PVCs are significantly related with a 1.90-fold higher incidence of AF, according to the present systematic review and meta-analysis. Nonetheless, further research is needed to determine how this connection should be treated in clinical practice if it is causal.

Relationship between premature ventricular complexes and stroke mortality in the general population

OBJECTIVES

Predictors for increased stroke mortality identify those who may need closer monitoring and better hospital care. While the link between premature ventricular complexes (PVCs) and incident ischemic stroke has been reported, studies on the association with fatal stroke are non-existent.

MATERIALS AND METHODS

We examined the association of PVCs with stroke mortality in 8047 participants (56.5 ± 0.39 years, 53% women, 80.9% Non-Hispanic Whites) without prior history of stroke from the Third National Health and Nutrition Examination Survey. National Death Index was used to identify the date and cause of death. PVCs were detected from 12‑lead standard electrocardiograms. Cox proportional hazard analysis was used to examine the association between any PVC with stroke mortality.

RESULTS

Approximately 2.1% (n = 134) participants had PVCs at baseline. Over a median follow-up of 22 years, 337 fatal strokes occurred. More strokes occurred in participants with baseline PVCs compared to those without (unadjusted cumulative incidence of stroke 9.5% vs. 2.5% respectively, p-value 0.001). In a multivariable-adjusted model, the presence of PVC was associated with an increased risk of stroke mortality (HR (95%CI): 2.50 (1.15-5.43). This association was stronger in participants with coronary heart disease (CHD) than those without it (HR (95%CI): 5.98 (2.2-16.2) vs. 1.97 (0.75-5.1) respectively; interaction-p = 0.008).

CONCLUSIONS

PVCs are associated with an increased risk of stroke mortality, especially among individuals with CHD. Whether improved hospital care or modifying PVCs could change outcomes should be examined in prospective studies.

Evaluation of patients with high burden of premature ventricular contractions by comprehensive transthoracic echocardiography

Background

The prevalence and prognosis of premature ventricular contractions (PVCs) among individuals without structural heart disease are uncertain. Standard transthoracic echocardiography is a common method in evaluation of underlying cardiovascular disease and is recommended as a diagnostic method in PVC patients. However, it is unclear whether comprehensive echocardiographic examination can identify pathological findings in PVC patients with a normal standard echocardiogram.

Method

We included forty consecutive patients with a high PVC burden (>10,000 PVCs/day) and normal findings at a standard echocardiogram and exercise test. All subjects were investigated by a comprehensive echocardiographic examination using parameters usually not included in a routine work-up. We compared the results with 22 age and sex-matched controls.

Results

In six additional parameters-global longitudinal strain, right ventricular strain, septal-lateral delay, ventricular-arterial coupling, integrated backscatter and left atrial activation time-a statistically significant difference was shown between PVC patients and controls. Among these parameters, global longitudinal strain had a high reliability between operators.

Conclusions

Despite normal findings at standard echocardiography, the PVC group showed signs of impaired heart function when more comprehensive echocardiography parameters were used.

Left ventricular dyssynchrony as marker of early dysfunction in premature ventricular contraction-induced cardiomyopathy

Background

Strain imaging has been suggested as a tool to detect early left ventricular (LV) dysfunction due to frequent premature ventricular contractions (PVCs) in patients with preserved LV ejection fraction (EF). However, the progression of intraventricular dyssynchrony (IVD), radial, and circumferential strain (RS, CS) in PVC-cardiomyopathy (CM) are unknown. The aim of this study was to elucidate the progression patterns of CS, IVD, and electro-mechanical latency (EML) in PVC-CM.

Methods and results

Pacemakers were implanted in 20 canines to reproduce ventricular bigeminy at 200ms (PVCs n = 11) for 12 weeks and compared to a sham group (n = 9). We obtained echocardiograms at baseline, 4-, 8- and 12-weeks. RS and CS were obtained at the LV mid-cavitary level. IVD was defined as the time between the earliest and latest peak RS. EML was defined as the time between the onset of QRS and the earliest peak RS. LVEF (62 ± 5 to 42 ± 7%, p < 0.01), CS (-18 ± 3 to -12 ± 3, p < 0.01), and EML (219 ± 37 to 283 ± 46ms, p = 0.02) changed significantly in the PVC group. Peak CS (-18 ± 3 to -14 ± 4, p = 0.02) and IVD (49 ± 31 to 122 ± 103, p = 0.05) had a significant change at 4-weeks despite preserved LVEF (51 ± 5%). IVD normalized while EML increased at weeks 8 and 12.

Conclusion

Our findings consolidate the existing theory that changes in strain precede changes in LVEF in PVC-CM. While IVD becomes abnormal early in the development of PVC-CM, it pseudo-normalizes at advanced stages due to further increases in EML suggestive of cardiac contractility remodeling. These findings are consistent with recent published data where abnormal LV mechanics could be part of a substrate that can predispose to worse outcome in PVC-Cardiomyopathy.

Arrhythmia-induced Cardiomyopathy: An Article Review

Arrhythmia is one of the significant reversible causes in patients with heart disease and left ventricular dysfunction. Tachycardia, atrial fibrillation, and premature ventricular contractions have indeed been related to arrhythmia-induced cardiomyopathy (CM), a reversible dilated CM. Effective arrhythmia suppression will entirely or partially recover ventricular function, lowering morbidity and mortality. However, the importance of arrhythmia-induced CM (ARiCM) is often underestimated in clinical practice because arrhythmia is often seen as a result rather than a cause of CM, leading in treatment delays and failure to increase the quality of life and better clinical outcomes. This article review aims to summarize the pathomechanisms, and a general approach to the management of ARiCM and its long-term outcomes. ARiCM can cause a variety of clinical signs, ranging from asymptomatic to severe heart failure symptoms. Electrocardiogram, 24 h Holter monitoring, echocardiography, and cardiac magnetic resonance are all recommended for diagnosis. More research is required to better understand the pathogenesis of ARiCM and to differentiate treatment alternatives to choose the ideal ARiCM management approach.

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.

Melissa officinalis tea favourably affects the frequency of premature ventricular beats and cardiometabolic profile among patients with premature ventricular contraction: A randomised open-label controlled trial

BACKGROUND AND AIMS

Premature ventricular contraction (PVC) as one of the most common arrhythmias could worsen the morbidity of cardiovascular events, particularly concurrent with other risk factors. Considering the probable side effects of antiarrhythmic drugs chronic use, prescribing herbal medicines for such conditions is on the rise. Melissa officinalis (MO) is widely identified as an antiarrhythmic and cardioprotective agent but there is limited evidence for its clinical use. This research, thus, aimed to investigate the effects of MO tea among patients with PVCs.

METHODS

The present 12-week randomised controlled trial enrolled 60 patients with confirmed diagnosis of moderate to low-grade PVCs. The patients in intervention group received MO teabags (containing 2-g dried leaves/250 mL in hot water) two times/day in addition to lifestyle modification recommendations, while control group only received lifestyle modification recommendations. After collecting the data, blood samples were gathered to explore serum concentrations of glucose and lipid markers. The number of premature ventricular beats and heart rates was determined by 24-hour rhythm Holter monitoring.

RESULTS

On average, the patients aged 47 years and approximately 67.8% (n = 40) were women. The ANCOVA adjusted for baseline values and confounders revealed that patients in the MO tea group had significantly lower concentrations of triglyceride (adjusted mean (AM) = 144.75 mg/dL), total cholesterol (AM = 155.35 mg/dL), and fasting blood sugar (AM = 90.85 mg/dL), compared with the controls (AM = 174.27, 171.99, 99.84 mg/dL, respectively (P-value ≤.042). However, the intervention failed to affect LDL-C and HDL-C levels significantly. Significantly reduced frequency of 24-hour premature ventricular beats in the MO tea group (AM = 2142.39) was also noted compared with the controls (AM = 3126.05); (P-value = .017). The 24-hour heartbeats showed only a significant decrease within the intervention group (P-value < .01).

CONCLUSION

Together, these results seem to support the higher cardioprotective effects of MO as a medicinal plant than lifestyle modifications alone. Nevertheless, further exploration of this hypothesis is warranted using large-scaled clinical trials.

Association of premature ventricular complexes and risk of ischemic stroke: A systematic review and meta-analysis

Recent studies have suggested that patients with premature ventricular complexes (PVCs) may have a higher risk of ischemic stroke. However, the data are limited and inconclusive. We conducted a systematic review and meta‐analysis to investigate the association between PVCs and the risk of ischemic stroke. A comprehensive literature review was conducted by searching for published articles indexed in MEDLINE and EMBASE databases from inception through September 25, 2020, to identify studies that compared the risk of ischemic stroke between patients with PVCs and individuals without PVCs. Pooled risk ratio (RR) and 95% confidence interval (CI) were calculated using a random‐effect, generic inverse variance method of Dersimonian and Laird. A total of four observational studies (2 prospective and 2 retrospective cohort studies) with 42 677 participants met the eligibility criteria and were included in the meta‐analysis. We found that patients with PVCs have a significantly higher risk of ischemic stroke than individuals without PVCs with the pooled RR of 1.31 (95% CI, 1.07–1.60, I² = 43%). From our systematic review and meta‐analysis, we found that PVCs are associated with a higher risk of ischemic stroke. Whether this association is causal and how it should be addressed in clinical practice require further investigations.

Association of Ventricular Arrhythmias With Dementia: The Atherosclerosis Risk in Communities (ARIC) Study

OBJECTIVE

We performed a cross-sectional analysis to determine whether nonsustained ventricular tachycardia (NSVT) and premature ventricular contractions (PVCs) were associated with dementia in a population-based study.

METHODS

We included 2,517 (mean age 79 years, 26% Black) participants who wore a 2-week ambulatory continuous ECG recording device in 2016 to 2017. NSVT was defined as a wide-complex tachycardia ≥4 beats with a rate >100 bpm. We calculated NSVT and PVC burden as the number of episodes per day. Dementia was adjudicated by experts. We used logistic regression to assess the associations of NSVT and PVCs with dementia.

RESULTS

The mean recording time of the Zio XT Patch was 12.6 ± 2.6 days. There were 768 (31%) participants with NSVT; prevalence was similar in White and Black participants. There were 134 (6.5%) dementia cases (5% in White, 10% in Black participants). After multivariable adjustment, there was no overall association between NSVT and dementia; however, there was a significant race interaction (p < 0.001). In Black participants, NSVT was associated with a 3.67 times higher adjusted odds of dementia (95% confidence interval [CI] 1.92-7.02) compared to those without NSVT, whereas in White participants NSVT was not associated with dementia (odds ratio [95% CI] 0.64 [0.37-1.10]). In Black participants only, a higher burden of PVCs was associated with dementia.

CONCLUSIONS

Presence of NSVT and a higher burden of NSVT and PVCs are associated with dementia in elderly Black people. Further research to confirm this novel finding and to elucidate the underlying mechanisms is warranted.

[The method for prediction of high-grade premature ventricular contractions in patients with heart failure and preserved ejection fraction]

Aim To develop a method for prediction of high-grade ventricular extrasystole (VE) in patients with chronic heart failure with preserved ejection fraction (CHF-PEF) based on results of an echocardiography (EchoCG) study.Material and methods At the first step, the study included 121 patients of the Cardiology Department, Municipal Clinical Hospital #31, St. Petersburg (calculation group) with symptoms and clinical signs of CHF-PEF (median age, 62 years). For testing accuracy of the developed formula, a control group was formed, which consisted of 42 patients with CHF-PEF (median age, 59 years). EchoCG at rest and ECG Holter monitoring were performed for all patient. The VE classification according to B. Lown and M. Wolf (1971) in the M. Ryan (1975) modification was used. Results of the evaluation were determined by the most significant recorded grade. Grade III or higher VE were considered as high-grade VE.Results Using logistic regression analysis of data for patients of the calculation group, a statistical model was constructed and a respective formula was developed to predict a probability of high-grade VE in CHF-PEF patients depending on the presence of risk factors (EchoCG criteria). According to the obtained data the following factors primarily contributed to the model: interventricular septal (IVS) thickness (p=0.007; Wald=7.44), end-diastolic volume index (EDVI) (p=0.044; Wald=4.13), and the degree of diastolic dysfunction (DD) (p&lt;0.0001; Wald=19.90). For testing the formula accuracy, the analysis was performed in the control group. Based on data of both stages, the following values were obtained: for the calculation group, the method sensitivity was 77.8 %, the specificity was 82.4 %, the accuracy was 81.0 %; for the control group, 81.8 %, 70 %, and 76.2 %, respectively; for both groups together, 79.3 %, 80.0 %, and 79.8 %, respectively. In ROC-analysis of this prognostic model, the area under the ROC-curve (AUC) was 0.852 (95 % CI: 0.776-0.910; p&lt;0.0001) for the calculation group; 0.818 (95 % CI: 0.669-0.920; p&lt;0.0001) for the control group; and 0.855 (95 % CI: 0.792-0.905; p&lt;0.0001) for both groups together, which indicated a good quality of the prognostic model.Conclusion The EchoCG predictors of high-grade VE in patients with CHF-PEF included degree of DD, EDVI, and IVS thickness. The developed method with the constructed formula for prediction of high-grade VE in CHF-PEF patients showed high sensitivity, specificity and accuracy.

Arrhythmia-Induced Cardiomyopathy: JACC State-of-the-Art Review

Arrhythmias coexist in patients with heart failure (HF) and left ventricular (LV) dysfunction. Tachycardias, atrial fibrillation, and premature ventricular contractions are known to trigger a reversible dilated cardiomyopathy referred as arrhythmia-induced cardiomyopathy (AiCM). It remains unclear why some patients are more prone to develop AiCM despite similar arrhythmia burdens. The challenge is to determine whether arrhythmias are fully, partially, or at all responsible for an observed LV dysfunction. AiCM should be suspected in patients with mean heart rate >100 beats/min, atrial fibrillation, and/or premature ventricular contractions burden ≥10%. Reversal of cardiomyopathy by elimination of the arrhythmia confirms AiCM. Therapeutic choice depends on the culprit arrhythmia, patient comorbidities, and preferences. Following recovery of LV function, patients require continued follow-up if an abnormal myocardial substrate is present. Appropriate diagnosis and treatment of AiCM is likely to improve quality of life and clinical outcomes and to reduce hospital admission and health care spending.

Is There any Relationship Between Myocardial Repolarization Parameters and the Frequency of Ventricular Premature Contractions?

BACKGROUND

Ventricular premature contractions (VPCs) may trigger lethal ventricular arrhythmias in patients with structural heart disease. However, this role of VPCs in healthy people remains controversial once that not enough clinical trials are available. Recently, some myocardial repolarization markers, such as Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios, have been reported to be useful for predicting lethal ventricular arrhythmias in various clinical disorders without structural heart disease.

OBJECTIVE

In this study, we aimed to investigate the relation between VPC frequent and myocardial repolarization markers in individuals without structural heart disease.

METHODS

This study included 100 patients who had complaints of dizziness and palpitations. Twelve-lead electrocardiography and 24-hour ambulatory Holter recordings were obtained from all patients. VPC burden was calculated as the total number of VPCs divided by the number of all QRS complexes in the total recording time. P-values < 0.05 were considered significant.

RESULTS

Tp-e interval and Tp-e/QTc ratio were significantly higher in patients with higher VPC burden than in patients with lower VPC burden, and a positive correlation was found between these markers and VPC burden. Tp-e (β = 1.318, p = 0.043) and Tp-e/QTc (β = -405.136, p = 0.024) in the lead V5 were identified as independent predictors of increased VPC burden.

CONCLUSIONS

Tp-e interval and Tp-e/QTc ratio increased in patients with high VPC number. Our study showed that VPCs may have a negative effect on myocardial repolarization. This interaction may lead to an increased risk of malignant arrhythmias.

Association of frequent premature ventricular complex >10% and stroke-like symptoms without a prior diagnosis of stroke or transient ischemic attack

Introduction

Premature ventricular complex (PVCs) detected from long-term ECG recordings have been associated with an increased risk of ischemic stroke. However, there was limited data about the association between high PVCs burdens (>10%) and stroke-like symptoms without a prior diagnosis of stroke or transient ischemic attack in the long-term follow up.

Methods

The Kosin University 24-hours holter monitoring, echocardiography, electrocardiogram (ECG) database were reviewed from 2013 to 2015 to identify patients with frequent PVCs (>10%). We compared the long-term clinical outcomes between the patients with frequent PVCs (>10%) and control group without PVC.

Results

Among 572 patients who underwent 24-hours holter monitoring, finally, 373 consecutive patients (mean age; 59.5 ± 15.8 years, 45.2% male) were enrolled. Among them, 203(54.4%) patients had high PVCs burdens (>10%). There was no difference of the baseline characteristics. In the long term follow-up, PVCs burden was not associated with PVCs -related symptoms (P = 0.210). In univariate analysis, female, non-sustained ventricular tachycardia (VT), sinus QRS duration, PVC coupling interval (CI), post- PVC CI, and late precordial R-wave transition of PVCs were associated with PVCs-related symptoms. In multivariate analysis, non-sustained VT (P = 0.022) and late precordial R-wave transition of PVCs (P = 0.044) were independent risk factors for PVCs-related stroke-like symptoms with frequent idiopathic PVCs > 10%.

Conclusion

High PVCs burdens (>10%) were associated with and stroke-like symptoms without a prior diagnosis of stroke or transient ischemic attack in the long-term follow up, suggesting more intensive medical therapy with close clinical follow-up will be required.

Premature ventricular contraction-induced cardiomyopathy in children

BACKGROUND

Adults with high premature ventricular contraction burden can develop left ventricular dilation, dysfunction, and strain, consistent with a cardiomyopathy, which is reversible with radiofrequency ablation of the premature ventricular contractions. Evidence in children with similar ectopy burden is limited. We performed a single-centre retrospective review to examine the prevalence of premature ventricular contraction-induced cardiomyopathy, natural history of ventricular ectopy, and progression to ventricular tachycardia in children with frequent premature ventricular contractions.

METHODS

Children aged between 6 months and 18 years, with premature ventricular contractions comprising at least 20% of rhythm on 24-hour Holter monitor, were included in our study. Those with significant structural heart disease, ventricular tachycardia greater than 1% of rhythm at the time of premature ventricular contraction diagnosis, or family history of cardiomyopathy - except tachycardia-induced - were excluded. Cardiomyopathy was defined by echocardiographic assessment.

RESULTS

A total of 36 children met the study criteria; seven patients (19.4%, 95% CI 6.2-32.6%) met the criteria for cardiomyopathy, mostly at initial presentation. Ectopy decreased to <10% of beats without intervention in 16.7% (95% CI 4.3-29.1%) of the patients. No patient progressed to having ventricular tachycardia as more than 1% of beats on follow-up Holter. Radiofrequency ablation was performed in three patients without cardiomyopathy.

CONCLUSIONS

Our study demonstrates a higher prevalence of cardiomyopathy among children with high premature ventricular contraction burden than that previously shown. Ectopy tended to persist throughout follow-up. These trends suggest the need for a multi-centre study on frequent premature ventricular contractions in children. In the interim, regular follow-up with imaging to evaluate for cardiomyopathy is warranted.

Abnormal Left Ventricular Mechanics of Ventricular Ectopic Beats: Insights Into Origin and Coupling Interval in Premature Ventricular Contraction-Induced Cardiomyopathy

BACKGROUND

Left ventricular (LV) dyssynchrony caused by premature ventricular contractions (PVCs) has been proposed as a mechanism of PVC-induced cardiomyopathy. We sought to understand the impact of different PVC locations and coupling intervals (prematurity) on LV regional mechanics and global function of the PVC beat itself.

METHODS AND RESULTS

Using our premature pacing algorithm, pentageminal PVCs at coupling intervals of 200 to 375 ms were delivered from the epicardial right ventricular apex, RV outflow tract, and LV free wall, as well as premature atrial contractions, from the left atrial appendage at a coupling interval of 200 ms in 7 healthy canines. LV short-axis echocardiographic images, LV stroke volume, and dP/dtmax were obtained during all ectopic beats and ventricular pacing. LV dyssynchrony was assessed by dispersion of QRS-to-peak strain (earliest-last QRS-to-peak strain) between 6 different LV segments during each of the aforementioned beats (GE, EchoPac). LV dyssynchrony was greater during long-coupled rather than short-coupled PVCs and PVCs at 375 ms compared with rapid ventricular pacing at 400 ms (P<0.0001), whereas no difference was found between PVC locations. Longer PVC coupling intervals were associated with greater stroke volume and dP/dtmax despite more pronounced dyssynchrony (P<0.001).

CONCLUSIONS

PVCs with longer coupling intervals demonstrate more pronounced LV dyssynchrony, whereas PVC location has minimal impact. LV dyssynchrony cannot be attributed to prematurity or abnormal ventricular activation alone, but rather to a combination of both. This study suggests that late-coupled PVCs may cause a more severe cardiomyopathy if dyssynchrony is the leading mechanism responsible for PVC-induced cardiomyopathy.

Premature ventricular complexes on screening electrocardiogram and risk of ischemic stroke

BACKGROUND AND PURPOSE

Premature ventricular complexes (PVCs) detected from long-term ECG recordings have been associated with an increased risk of ischemic stroke. Whether PVCs seen on routine ECG, commonly used in clinical practice, are associated with an increased risk of ischemic stroke remains unstudied.

METHODS

This analysis included 24 460 participants (aged, 64.5+9.3 years; 55.1% women; 40.0% blacks) from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study who were free of stroke at the time of enrollment. PVCs were ascertained from baseline ECG (2003-2007), and incident stroke cases through 2011 were confirmed by an adjudication committee.

RESULTS

A total of 1415 (5.8%) participants had at least 1 PVC at baseline, and 591 developed incident ischemic stroke during an average (SD) follow-up of 6.0 (2.0) years. In a cox proportional hazards model adjusted for age, sex, race, geographic region, education, previous heart disease, systolic blood pressure, blood pressure-lowering medications, current smoking, diabetes mellitus, left ventricular hypertrophy by ECG, and aspirin use and warfarin use, the presence of PVCs was associated with 38% increased risk of ischemic stroke (hazard ratio [95% confidence interval], 1.38 [1.05-1.81]).

CONCLUSIONS

PVCs are common on routine screening ECGs and are associated with an increased risk of ischemic stroke.

Adenosine sensitivity is associated with ablation success rate and recurrence rate with nonirrigated catheters in patients with ventricular premature contractions/tachycardia from the ventricular outflow tract

BACKGROUND

A high ablation success rate for ventricular arrhythmia (VA) from outflow tract has been achieved, but some of them cannot be eliminated from endocardium. We investigated the association between adenosine sensitivity and ablation success/recurrence rates with a nonirrigated or an irrigated catheter.

METHODS

According to adenosine test, all patients were divided into a sensitive group (S group) or an insensitive group (I group). The patients of each group were randomized into a nonirrigated catheter (NA) subgroup or an irrigated catheter (IA) subgroup with a 2:1 ratio.

RESULTS

In S group of 122 patients (84 in NA subgroup), the ablation success rate was similar between two subgroups (94.7% vs. 90.5%, P > 0.05), but in I group of 94 patients (60 in NA subgroup), it was higher in IA subgroup (94.1%) than that in NA subgroup (73.3%, P < 0.05). The success rate using nonirrigated catheter was significantly higher in S group (90.5%) than that in I group (73.3%, P < 0.01), and the recurrence rate was lower in S group than that in I group (1.3%, vs. 13.6%, P < 0.05). On the contrary, the success rate and the recurrence rate using irrigated catheter were similar between S group and I group (94.7%, 94.1%, P > 0.05, vs. 2.8%, 6.3%, P > 0.05).

CONCLUSIONS

Adenosine insensitivity is associated with a lower success rate and a higher recurrence rate for VA patients undergoing nonirrigated catheter ablation. Thus, irrigated catheters should be the first choice for VA ablation in adenosine insensitive patients.

Outflow tract premature ventricular depolarizations after atrial fibrillation ablation may reflect autonomic influences

PURPOSE

Autonomic modulation following catheter ablation of atrial fibrillation may promote the development of catecholamine-sensitive arrhythmias, such as outflow tract (OT) ventricular premature depolarizations (VPDs). The purpose of this study was to determine the incidence and prognostic significance of OT VPDs occurring in patients after atrial fibrillation (AF) ablation.

METHODS

We prospectively examined 53 consecutive patients undergoing wide-area circumferential antral pulmonary vein (PV) isolation; no patients had evidence of OT VPDs on 24 h of preprocedural telemetry monitoring. Cases (OT+) had postprocedure telemetry monitoring with >30 continuous beats or >3/min OT VPDs. Clinical follow-up included transtelephonic monitoring at 6 weeks, 6 months, and 1 year.

RESULTS

The incidence of OT VPDs in this population was 11% (6/53). There was no difference in AF recurrence at 1 year between those with or without OT VPDs (17 vs 28%, p = 0.6). There was a strong association with higher immediate postprocedure heart rate (HR) in OT+ compared to OT- patients (86 vs 76, p = 0.03); this difference persisted at 1 year (79 vs 60, p < 0.01). OT VPDs resolved in 5/6 of the OT+ patients over the 1-year follow-up. In a multivariable linear regression model, OT VPDs were associated with higher HR (odds ratio (OR) 1.14 [1.10-1.18], p < 0.001) despite adjustment for medication dose.

CONCLUSIONS

A minority of patients undergoing antral PV isolation develops OT VPDs associated with a sustained increase in mean heart rate; this effect may result from the modulation of adjacent autonomic ganglia.

Relation of ventricular premature complexes to heart failure (from the Atherosclerosis Risk In Communities [ARIC] Study)

Analogous to rapid ventricular pacing, frequent ventricular premature complexes (VPCs) can predispose over time to cardiomyopathy and subsequent heart failure (HF). We examined the association of frequent VPCs with HF incidence in a population-based cohort, free of HF and coronary heart disease at baseline. At study baseline (1987 to 1989), ≥1 VPC on a 2-minute rhythm electrocardiographic strip was seen in 5.5% (739 of 13,486) of the middle-age (45 to 64 years old at baseline) white and black, men and women of the Atherosclerosis Risk In Communities cohort. Incident HF was defined as the first appearance of International Classification of Diseases code 428.x in the hospital discharge record or death certificate through 2005. During an average follow-up of 15.6 years, incident HF was seen in 10% the participants (19.4% of those with VPCs vs 9.4% of those without). The age-, race-, and gender-adjusted hazard ratio of HF for VPCs was 1.89 (95% confidence interval 1.59 to 2.24). After multivariable adjustment for potential confounders, the hazard ratio of HF for those with any VPC versus no VPC was 1.63 (95% confidence interval 1.36 to 1.96). After additional adjustment for incident coronary heart disease as a time-varying covariate, the hazard ratio was 1.71 (95% confidence interval 1.42 to 2.08). Those with a greater frequency of VPCs or complex VPCs had similar rates of HF compared to those with a single VPC and all had rates greater than those with no VPC. In conclusion, in this large population-based cohort, the presence of VPCs was associated with incident HF, independent of incident coronary heart disease.

Left ventricular systolic dysfunction induced by ventricular ectopy: a novel model for premature ventricular contraction-induced cardiomyopathy

BACKGROUND

Premature ventricular contractions (PVCs) commonly coexist with cardiomyopathy. Recently, PVCs have been identified as a possible cause of cardiomyopathy. We developed a PVC-induced cardiomyopathy animal model using a novel premature pacing algorithm to assess timeframe and reversibility of this cardiomyopathy and examine the associated histopathologic abnormalities.

METHODS AND RESULTS

Thirteen mongrel dogs were implanted with a specially programmed pacemaker capable of simulating ventricular extrasystoles. Animals were randomly assigned to either 12 weeks of bigeminal PVCs (n = 7) or no PVCs (control, n = 6). Continuous 24-hour Holter monitoring corroborated ventricular bigeminy in the PVC group (PVC, 49.8% versus control, < 0.01%; P<0.0001). After 12 weeks, only the PVC group had cardiomyopathy, with a significant reduction in left ventricular ejection fraction (PVC, 39.7 ± 5.4% versus control, 60.7 ± 3.8%; P < 0.0001) and an increase in left ventricular end-systolic dimension (PVC, 33.3 ± 3.5 mm versus control, 23.7 ± 3.6 mm; P < 0.001). Ventricular effective refractory period showed a trend to prolong in the PVC group. PVC-induced cardiomyopathy was resolved within 2 to 4 weeks after discontinuation of PVCs. No inflammation, fibrosis, or changes in apoptosis and mitochondrial oxidative phosphorylation were observed with PVC-induced cardiomyopathy.

CONCLUSIONS

This novel PVC animal model demonstrates that frequent PVCs alone can induce a reversible form of cardiomyopathy in otherwise structurally normal hearts. PVC-induced cardiomyopathy lacks gross histopathologic and mitochondrial abnormalities seen in other canine models of cardiomyopathy.

Premature ventricular complexes and the risk of incident stroke: the Atherosclerosis Risk In Communities (ARIC) Study

BACKGROUND AND PURPOSE

Premature ventricular complexes (PVCs) on a 2-minute electrocardiogram are a common, largely asymptomatic finding associated with increased risk of coronary heart disease and death. They may reflect atherosclerosis or other pathogenic pathways that predispose to arrhythmias and stroke.

METHODS

We conducted a prospective evaluation of the Atherosclerosis Risk In Communities Study cohort (n=14,783) of middle-aged men and women to assess whether the presence of PVCs at study baseline (1987 to 1989) influenced the risk of incident stroke through December 31, 2004.

RESULTS

PVCs were seen in 6.1% of the participants at baseline, and 729 (4.9%) had incident stroke. The unadjusted cumulative proportion of incident stroke in individuals with any PVC was 6.6% compared with 4.1% in those without PVC. The unadjusted hazard ratio of incident stroke in individuals with any PVC compared with those without any PVCs was 1.71 (95% CI, 1.33 to 2.20). Among individuals without hypertension and diabetes at baseline, PVCs were independently associated with incident stroke (hazard ratio: 1.72; 95% CI: 1.14 to 2.59). Among those with either diabetes or hypertension, the presence of any PVCs did not increase the risk of stroke. The association was stronger for noncarotid embolic stroke than for thrombotic stroke and its magnitude increased with higher frequency of PVCs.

CONCLUSIONS

Frequent PVCs are associated with risk of incident stroke in participants free of hypertension and diabetes. This suggests that PVCs may contribute to atrioventricular remodeling or may be a risk marker for incident stroke, particularly embolic stroke.

Predictors of ventricular arrhythmias in patients with mitral valve prolapse

Arrhythmias have been reported to occur frequently in symptomatic patients with mitral valve prolapse (MVP). The mechanisms causing ventricular arrhythmias in patients with MVP have not been fully investigated. The purpose of this study was to determine the clinical, echocardiographic and heart rate variability parameters, and plasma concentrations of electrolytes and inflammatory markers in predicting ventricular arrhythmias in patients with MVP. A total of 58 consecutive patients with MVP were included in this study. We performed electrocardiography, echocardiography, holter analysis, routine biochemical tests including plasma concentrations of electrolytes and inflammatory markers, and evaluated the clinical characteristics. Ventricular arrhythmia defined as occurrence of any of the followings: ventricular premature contractions (VPCs), VPC couplets, and ventricular tachycardia documented by holter analysis, continuous monitoring or by electrocardiography. Twenty patients (34%) had ventricular arrhythmias, and 38 (66%) patients had no ventricular arrhythmias. Seventeen patients had VPC, 2 patients had VPC couplets and 1 patient had ventricular tachycardia. Univariable predictors of ventricular arrhythmias included isovolumetric relaxation time and the occurrence of moderate to severe mitral regurgitation. Multivariable logistic regression analysis showed that occurrence of moderate to severe mitral regurgitation was the only independent predictor of ventricular arrhythmias (relative risk: 8.42, 95% confidence interval: 1.49-47.64, p = 0.01). Present study showed that the only independent predictor of ventricular arrhythmias in patients with MVP is the occurrence of moderate to severe mitral regurgitation.

Comparative effects of levosimendan and dobutamine on right ventricular function in patients with biventricular heart failure

Severe heart failure represents a major source of morbidity and mortality. Poor right ventricular function is an independent prognostic marker for mortality in patients with chronic heart failure. In this study, levosimendan (L) and dobutamine (D) in patients with severe chronic biventricular failure were compared. Forty consecutive patients, who were judged for inotropic therapy by their primary physicians, with acutely decompensated systolic heart failure and having moderate-to-severe right ventricular dysfunction with right ventricular fractional area change of Collapse

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MESH Headings

• Aged
• Cardiotonic Agents/administration & dosage
• Diastole
• Dobutamine/administration & dosage
• Dose-Response Relationship, Drug
• Echocardiography
• Female
• Follow-Up Studies
• Heart Failure/diagnostic imaging
• Heart Failure/drug therapy
• Heart Failure/physiopathology
• Heart Ventricles/diagnostic imaging
• Heart Ventricles/drug effects
• Heart Ventricles/physiopathology
• Humans
• Hydrazones/administration & dosage
• Infusions, Intravenous
• Male
• Middle Aged
• Pyridazines/administration & dosage
• Simendan
• Stroke Volume/drug effects
• Stroke Volume/physiology
• Systole
• Treatment Outcome
• Ventricular Dysfunction, Right/diagnostic imaging
• Ventricular Dysfunction, Right/drug therapy
• Ventricular Dysfunction, Right/physiopathology
• Ventricular Function, Right/drug effects
• Ventricular Function, Right/physiology

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Affiliation(s)

Mehmet Birhan Yilmaz Department of Cardiology, Cumhuriyet University School of Medicine, L Blok Daire 1, 58140 Sivas, Turkey.
Can Yontar
Alim Erdem
Filiz Karadas
Kenan Yalta
Okan Onur Turgut
Ahmet Yilmaz
Izzet Tandogan

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Comparison of myocardial performance index obtained either by conventional echocardiography or tissue Doppler echocardiography in healthy subjects and patients with heart failure

This study was planned to investigate the normal reference values of myocardial performance index (MPI) obtained by tissue Doppler echocardiography (TDE) and the agreement between MPI measured by TDE and conventional MPI measured by pulsed-wave Doppler (PWD) in healthy subjects and patients with heart failure (HF). Two hundred and three patients with HF and 190 healthy subjects were enrolled in this study. Isovolumic contraction and relaxation time (ICT and IRT) and ejection time (ET) were measured from mitral inflow and left ventricular (LV) outflow. Tissue Doppler echocardiography recordings were obtained at the septal, lateral, inferior, and anterior of the mitral annulus and same time intervals were measured. Myocardial performance index was calculated. The functional capacity of the patients with HF was determined according to New York Heart Association classification. TDE-MPI values were higher than conventional PWD-MPI values in both groups (53%+/-8% vs 48%+/-11%, P<0.0001 in the healthy subjects; 84%+/-21% vs 72%+/-19%, P<0.0001 in the patients with HF). Moderate agreement was found between PWD-MPI and LV mean TDE-MPI in both groups. In identifying patients with moderately or severely decreased LV ejection fraction, TDE-MPI had higher cutoff values than conventional PWD-MPI, and TDE-MPI had higher specificity, sensitivity, negative predictive value, and diagnostic accuracy. In patients with HF, TDE-MPI had a stronger correlation with LV ejection fraction and functional capacity than did PWD-MPI. TDE-MPI is an alternative to conventional PWD-MPI in assessment of cardiac function. However, the higher MPI cutoff points should be considered when this method is used for the evaluation of cardiac function.