Characteristics of Premature Ventricular Complexes as Correlates of Reduced Left Ventricular Systolic Function: Study of the Burden, Duration, Coupling Interval, Morphology and Site of Origin of PVCs

Premature ventricular complexes: Assessing burden density in a large national cohort to better define optimal ECG monitoring duration

BACKGROUND

Premature ventricular contraction (PVC) burden is a risk factor for heart failure and cardiovascular death in patients with structural heart disease. Long-term electrocardiographic monitoring can have a significant impact on PVC burden evaluation by further defining PVC distribution patterns.

OBJECTIVE

This study aimed to ascertain the optimal duration of electrocardiographic monitoring to characterize PVC burden and to understand clinical characteristics associated with frequent PVCs and nonsustained ventricular tachycardia in a large US cohort.

METHODS

Commercial data (iRhythm's Zio patch) from June 2011 to April 2022 were analyzed. Inclusion criteria were age >18 years, PVC burden ≥5%, and wear period ≥13 days. PVC burden cutoffs were determined on the basis of AHA/ACC/HRS guidelines for very frequent PVCs (10,000-20,000 during 24 hours). Patients were assigned to categories by PVC densities: low, <10%; moderate, 10% to <20%; and high, ≥20%. Mean measured error was assessed at baseline and daily until the wear period's end for overall PVC burden and different PVC densities.

RESULTS

Analysis of 106,705 patch monitors revealed a study population with mean age of 70.6 ± 14.6 years (33.6% female). PVC burden was higher in male patients and those >65 years of age. PVC burden mean error decreased from 2.9% at 24 hours to 1.3% at 7 days and 0.7% at 10 days. Number of ventricular tachycardia episodes per patient increased with increasing PVC burden (P < .0001).

CONCLUSION

Extending ambulatory monitoring beyond 24 hours to 7 days or more improves accuracy of assessing PVC burden. Ventricular tachycardia frequency and duration vary by initial PVC density, highlighting the need for prolonged cardiac monitoring.

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.

Number of Premature Ventricular Complexes Predicts Long-Term Outcomes in Patients with Persistent Atrial Fibrillation

BACKGROUND

Premature ventricular complexes (PVCs) are common electrocardiographic abnormalities and may be a prognosticator in predicting mortality in patients with structurally normal hearts or chronic heart diseases. Whether PVC burden was associated with mortality in patients with chronic atrial fibrillation (AF) remained unknown. We investigated the prognostic value of PVC burden in patients with persistent AF.

METHODS

A retrospective analysis of 24 h Holter recordings of 1767 patients with persistent AF was conducted. Clinical characteristics, 24 h average heart rate (HR), and PVC measures, including 24 h PVC burden and the presence of consecutive PVCs (including any PVC couplet, triplet, or non-sustained ventricular tachycardia) were examined for the prediction of all-cause and cardiovascular mortality using the Cox proportional hazards model.

RESULTS

After a median follow-up time of 30 months, 286 (16%) patients died and 1481 (84%) patients survived. Multivariate analysis revealed that age, heart failure, stroke, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, beta-blocker, digoxin, oral anticoagulant use, and estimated glomerular filtration rate were significant baseline predictors of all-cause mortality and cardiovascular mortality. Twenty-four-hour PVC burden and the presence of consecutive PVCs were significantly associated with all-cause and cardiovascular mortality after adjusting for significant clinical factors. When compared to the first quartile of PVC burden (<0.003%/day), the highest quartile (>0.3%/day) was significantly associated with an increased risk of all-cause mortality (hazard ratio, 2.46; 95% CI, 1.77-3.42) and cardiovascular mortality (hazard ratio: 2.67; 95% CI, 1.76-4.06).

CONCLUSIONS

Twenty-four-hour PVC burden is independently associated with all-cause and cardiovascular mortality in patients with persistent AF.

Premature Ventricular Contraction-Induced Cardiomyopathy: Contemporary Evidence from Risk Stratification, Pathophysiology, and Management

Premature ventricular complexes (PVCs) are commonly encountered problems in clinical settings. The range of symptoms can be from asymptomatic to palpitations, fatigue, or heart failure symptoms. A higher burden of PVCs is a risk factor for development of PVC-induced cardiomyopathy (PIC). Rhythm evaluation by 12-lead ECG and an ambulatory monitoring device are essential. Currently, several imaging modalities, such as echocardiography and cardiac magnetic resonance imaging, are utilized to evaluate the underlying structure that may be related to PIC. Beta blockers and antiarrhythmic drugs are typically part of the initial management strategy. If these fail, catheter ablation of PVCs is typically the next step. The purpose of this article is to summarize the current evidence/knowledge about PIC.

Propensity-score matched comparison of renal and neurohormonal effects of catheter ablation for frequent premature ventricular contractions in patients with and without systolic dysfunction

Background

Catheter ablation (CA) for premature ventricular contractions (PVCs) restores cardiac and renal functions in patients with reduced left ventricular ejection fraction (LVEF); however, its effects on preserved EF remain unelucidated.

Methods

The study cohort comprised 246 patients with a PVC burden of >10% on Holter electrocardiography. Using propensity matching, we compared the changes in B-type natriuretic peptide (BNP) levels and estimated glomerular filtration rate (eGFR) in patients who underwent CA or did not.

Results

Postoperative BNP levels were decreased significantly in the CA group, regardless of the degree of LVEF, whereas there was no change in those of the non-CA group. Among patients who underwent CA, BNP levels decreased from 44.1 to 33.0 pg/mL in those with LVEF ≥50% (p = .002) and from 141.0 to 87.9 pg/mL in those with LVEF <50% (p < .001). Regarding eGFR, postoperative eGFR was significantly improved in the CA group of patients with LVEF ≥50% (from 71.4 to 74.7 mL/min/1.73 m2, p = .006), whereas it decreased in the non-CA group. A similar trend was observed in the group with a reduced LVEF. Adjusted for propensity score matching, there was a significant decrease in the BNP level and recovery of eGFR after CA in patients with LVEF >50%.

Conclusions

This study showed that CA for frequent PVCs decreases BNP levels and increases eGFR even in patients with preserved LVEF.

Predictors and possible mechanisms of premature ventricular contraction induced cardiomyopathy

Premature ventricular complexes (PVCs) are encountered frequently in clinical practice. While PVCs may have various causes, a small number of individuals with PVCs develop cardiomyopathy in the absence of other potential etiologies. When correctly identified, patients with PVC-incuded cardiomyopathy can have dramatic improvement of their cardiomyopathy with treatment of their PVCs. In this focused review, we discuss potential predictors of PVC-induced cardiomyopathy, including PVC frequency, PVC characteristics, and modifiable patient risk factors. We also review some proposed mechanisms of PVC-induced cardiomyopathy and conclude with future directions for research and clinical practice.

Assessment of subtle cardiac dysfunction induced by premature ventricular contraction using two-dimensional strain echocardiography and the effects of successful ablation

INTRODUCTION AND OBJECTIVES

We aimed to assess the effects of successful ablation on impaired left ventricular global longitudinal strain (LV-GLS) in patients with frequent premature ventricular contractions (PVCs). We also evaluated the potential risk factors of impaired LV-GLS.

METHODS

Thirty-six consecutive patients without any structural heart disease, who were treated with radiofrequency (RF) ablation due to frequent PVCs, were included in the study. All patients were evaluated with standard transthoracic and two-dimensional speckle tracking echocardiography.

RESULTS

Mean LV-GLS before ablation was 17.3±3.7 and 20.5±2.6 after ablation; the difference was statistically significant (p<0.01). Patients were categorized into two groups: those with LV-GLS value >-16% and those ≤16%. Low PVC E flow/post-PVC E flow and PVC SV/post-PVC SV ratios were associated with impaired LV-GLS.

CONCLUSION

In symptomatic patients with frequent PVCs and normal left ventricular ejection fraction, we observed significant improvement in LV-GLS value following successful RF ablation. Patients with impaired LV-GLS more often display non-ejecting PVCs and post-extrasystolic potentiation (PEP) compared to patients with normal LV-GLS.

The significance of heart rate variability in patients with frequent premature ventricular complex originating from the ventricular outflow tract

BACKGROUND

As an indicator of cardiac autonomic nervous activity, heart rate variability (HRV) is closely linked to premature ventricular complexes (PVCs). However, its role in patients with frequent PVCs originating from the ventricular outflow tract remains unclear.

HYPOTHESIS

Here, we hypothesize that there may be alterations in HRV among patients with frequent PVCs originating from the ventricular outflow tract, which could play significant roles in the management of such patients.

METHODS

A retrospective study was conducted, including 106 patients with frequent outflow tract PVCs and 106 healthy participants as controls. HRV was assessed based on the 24-hour Holter recording. The originating foci of PVCs were identified during radiofrequency catheter ablation.

RESULTS

Patients with frequent outflow tract PVCs exhibited decreased levels of high frequency (HF), standard deviation of all NN intervals, and standard deviation of the average NN intervals, but increased ratios of low frequency to HF (LF/HF ratio), even after propensity score-matched analysis. Further investigation revealed that patients with PVCs originating from right ventricular outflow tract (RVOT) had much higher LF/HF ratios. Multivariate logistic regression analysis demonstrated that the LF/HF ratio was independently associated with PVCs originating from RVOT. Receiver operating characteristics curve indicated that the LF/HF ratio effectively determined the origin of PVCs (the area under the curve = 0.75, p < .001).

CONCLUSIONS

Patients with frequent outflow tract PVCs exhibited impaired HRV. Additionally, the LF/HF ratio played a significant role in determining the origin of outflow tract PVCs.

Association between excess catecholamine synthesis and polymorphic premature ventricular contraction

BACKGROUND

The reasons for the etiology of premature ventricular contractions (PVCs) are not specifically known. Many patients are resistant to medical treatment, and a factor that would predict response to medical treatment cannot be identified. This study aims to investigate if a high catecholamine level results in polymorphic PVC.

METHODS

This study was obtained by prospective data registry analysis. A total of 100 patients, 50 from the PVC group, and 50 from the control group have been evaluated. The participants who were included in the patient group had a polymorphic PVC of 5% or more in their 24-h Holter evaluations. Metanephrine showing the level of adrenaline and normetanephrine, showing the level of noradrenaline levels have been measured from these urine samples.

RESULT

There was no difference between the two groups in terms of biochemical and essential characteristics. Normetanephrine level has been significantly higher in the PVC group compared to the control group (323.9 ± 208.9 μg to 129.25 ± 67.88 μg; p < 0.001). Similarly, metanephrine level has also been higher in the PVC group (124.75 ± 82.43 μg to 52.615 ± 36,54 μg; p < 0.001). A positive and moderate correlation has been identified between the number and ratio of PVC and the metanephrine and normetanephrine levels.

CONCLUSION

In this study, we found that the catecholamine levels were higher in the polymorphic PVC group than in the healthy volunteers. Also, an increase in the number and rate of PVC has been observed as the catecholamine levels increased.

CLINICAL TRIAL REGISTRATION

Urine Levels of Metanephrine and Normetanephrine in Patients With Frequent PVC; ClinicalTrials.gov number NCT03447002.

An Early Indicator in Evaluating Cardiac Dysfunction Related to Premature Ventricular Complexes: Cardiorespiratory Capacity

Cardiac dysfunction induced by premature ventricular complexes (PVCs) is relatively controversial and challenging to detect in the early stage. In this observational study, we retrospectively analyzed the cardiopulmonary exercise test (CPET) data of 94 patients with frequent premature ventricular beats (47 males, 49.83 ± 13.63 years) and 98 participants (55 males, 50.84 ± 9.41 years) whose age and gender were matched with the patient with PVCs. The baseline information and routine echocardiography detection were recorded on admission. PVCs were diagnosed by 24 h Holter monitoring, and cardiorespiratory capacity was assessed using peak oxygen uptake (V'O2peak), anaerobic threshold (AT), and other CPET parameters with an individualized bicycle ramp protocol according to the predicted workload and exercise situation of each participant. There were no statistically significant differences in most baseline characteristics between the two groups. Indicators that reflect cardiopulmonary capacity, such as V'O2peak, AT, and ΔO2 pulse/Δwork rate(ΔV'O2/ΔWR), were all significantly lower in the PVC group (p = 0.031, 0.021, and 0.013, respectively) despite normal and nondiscriminatory left ventricular ejection fractions between the two groups. However, there was no statistically significant difference among subgroups based on the frequency of PVCs, which was <10,000 beats/24 h, 10,000-20,000 beats/24 h, and >20,000 beats/24 h. The cardiorespiratory capacity was lower in patients with frequent PVCs, indicating that CPET could detect early signs of impaired cardiac function induced by PVCs.

Left ventricular remodeling in premature ventricular contraction-induced cardiomyopathy: Effect of coupling intervals and atrioventricular dissociation

Background

Left ventricular dyssynchrony (LVD) and postextrasystolic potentiation (PESP) associated with premature ventricular contractions (PVCs) may play a role in the development of premature ventricular contraction-induced cardiomyopathy (PVC-CM). Long-coupled (LC) PVCs have a greater LVD than short-coupled (SC) PVCs, whereas SC-PVCs have a stronger PESP than LC-PVCs.

Objective

The purpose of this study was to compare SC-PVCs and LC-PVCs to evaluate the roles of LVD, PESP, and atrioventricular dissociation (AVD) in the development of PVC-CM.

Methods

Thirty-six canines underwent pacemaker implantation to induce bigeminal right ventricular apical epicardial PVCs (50% burden) for 12 weeks. Telemetry assessed PVC burden and AVD. Animals were grouped as SC-PVC (coupling interval [CI] 200-220ms), LC-PVC (CI 330 ms), or sham (control). Echocardiographic changes, AVD, and hemodynamics were monitored for 12 weeks.

Results

PVC burden was similar between SC-PVC and LC-PVC groups but was statistically higher in the SC-PVC group (50% vs 47.5%; P = .028). After 12 weeks, left ventricular ejection fraction (LVEF) significantly decreased in both SC-PVC and LC-PVC groups (47.1% ± 1.4% and 45.5% ± 2%, respectively) compared to sham group (61% ± 1.6%; P <.001). Overall AVD was similar between SC-PVC and LC-PVC groups, and there was no significant correlation between AVD and reduction in LVEF at 12 weeks (r = 0.09, P = .5; and r = 0.06, P = .8, respectively). Additionally, both SC-PVC and LC-PVC groups experienced substantial declines in max and min dP/dt after 12 weeks compared to baseline.

Conclusion

Neither PVC CI nor AVD played an independent role in the development or severity of PVC-CM. LVD and PESP make equal relative contributions to the development of PVC-CM.

A Novel ECG-Based Deep Learning Algorithm to Predict Cardiomyopathy in Patients With Premature Ventricular Complexes

BACKGROUND

Premature ventricular complexes (PVCs) are prevalent and, although often benign, they may lead to PVC-induced cardiomyopathy. We created a deep-learning algorithm to predict left ventricular ejection fraction (LVEF) reduction in patients with PVCs from a 12-lead electrocardiogram (ECG).

OBJECTIVES

This study aims to assess a deep-learning model to predict cardiomyopathy among patients with PVCs.

METHODS

We used electronic medical records from 5 hospitals and identified ECGs from adults with documented PVCs. Internal training and testing were performed at one hospital. External validation was performed with the others. The primary outcome was first diagnosis of LVEF ≤40% within 6 months. The dataset included 383,514 ECGs, of which 14,241 remained for analysis. We analyzed area under the receiver operating curves and explainability plots for representative patients, algorithm prediction, PVC burden, and demographics in a multivariable Cox model to assess independent predictors for cardiomyopathy.

RESULTS

Among the 14,241-patient cohort (age 67.6 ± 14.8 years; female 43.8%; White 29.5%, Black 8.6%, Hispanic 6.5%, Asian 2.2%), 22.9% experienced reductions in LVEF to ≤40% within 6 months. The model predicted reductions in LVEF to ≤40% with area under the receiver operating curve of 0.79 (95% CI: 0.77-0.81). The gradient weighted class activation map explainability framework highlighted the sinus rhythm QRS complex-ST segment. In patients who underwent successful PVC ablation there was a post-ablation improvement in LVEF with resolution of cardiomyopathy in most (89%) patients.

CONCLUSIONS

Deep-learning on the 12-lead ECG alone can accurately predict new-onset cardiomyopathy in patients with PVCs independent of PVC burden. Model prediction performed well across sex and race, relying on the QRS complex/ST-segment in sinus rhythm, not PVC morphology.

Prognostic impact of morphology and duration of premature ventricular contractions in a population without structural heart disease

BACKGROUND

Premature ventricular contractions (PVCs) are a common form of arrhythmia associated with an unfavorable prognosis in patients with structural heart disease. It is unclear whether PVCs site of origin and QRS-width has a prognostic significance in patients without structural heart disease. The aim of this study was to assess the prognostic importance of PVCs morphology and duration in this patient group.

METHODS

We included 511 consecutive patients without a history of previous heart disease. They were examined with echocardiography and exercise test with normal findings. We categorized the PVCs from a 12 lead ECG according to morphology and width of the QRS-complex and analyzed the outcome in terms of a composite endpoint of total mortality and cardiovascular morbidity.

RESULTS

During a median follow-up time of 5.3 years, 19 patients (3.5%) died and 61 (11.3%) met the composite outcome. Patients with PVCs originating from the outflow tracts had a significantly lower risk for the composite outcome compared to patients with non-OT-PVCs. Similarly, patients with PVC originating from the right ventricle had a better outcome than patients with left ventricular PCVs. No difference in outcome depending on QRS-width during PVCs was noticed.

CONCLUSION

In our cohort of consecutively included PVC patients without structural heart disease PVCs from the outflow tracts were associated with a better prognostic outcome than non-OT PVCs; the same was true for right ventricular PVCs when compared to left ventricular ones. The classification of the origin of the PVCs was based on 12-lead ECG morphology. QRS-width during PVC did not seem to have prognostic significance.

Catheter Ablation vs Antiarrhythmic Drug Therapy for Treatment of Premature Ventricular Complexes: A Systematic Review

There is variability in treatment modalities for premature ventricular complexes (PVCs), including use of antiarrhythmic drug (AAD) therapy or catheter ablation (CA). This study reviewed evidence comparing CA vs AADs for the treatment of PVCs. A systematic review was performed from the Medline, Embase, and Cochrane Library databases, as well as the Australian and New Zealand Clinical Trials Registry, U.S. National Library of Medicine ClinicalTrials database, and the European Union Clinical Trials Register. Five studies (1 randomized controlled trial) enrolling 1,113 patients (57.9% female) were analyzed. Four of five studies recruited mainly patients with outflow tract PVCs. There was significant heterogeneity in AAD choice. Electroanatomic mapping was used in 3 of 5 studies. No studies documented intracardiac echocardiography or contact force-sensing catheter use. Acute procedural endpoints varied (2 of 5 targeted elimination of all PVCs). All studies had significant potential for bias. CA seemed superior to AADs for PVC recurrence, frequency, and burden. One study reported long-term symptoms (CA superior). Quality of life or cost-effectiveness was not reported. Complication and adverse event rates were 0% to 5.6% for CA and 9.5% to 21% for AADs. Future randomized controlled trials will assess CA vs AADs for patients with PVCs without structural heart disease (ECTOPIA [Elimination of Ventricular Premature Beats with Catheter Ablation versus Optimal Antiarrhythmic Drug Treatment]), with impaired LVEF (PAPS [Prospective Assessment of Premature Ventricular Contractions Suppression in Cardiomyopathy] Pilot), and with structural heart disease (CAT-PVC [Catheter Ablation Versus Amiodarone for Therapy of Premature Ventricular Contractions in Patients With Structural Heart Disease]). In conclusion, CA seems to reduce recurrence, burden, and frequency of PVCs compared with AADs. There is a lack of data on patient- and health care-specific outcomes such as symptoms, quality of life, and cost-effectiveness. Several upcoming trials will offer important insights for management of PVCs.

Contemporary updates on ventricular arrhythmias: from mechanisms to management

Ventricular arrhythmias (VAs) are a group of heart rhythm disorders that can be life-threatening and cause significant morbidity. VA in the presence of structural heart disease (SHD) has distinct prognostic implications and requires a comprehensive and multifaceted approach for investigation and management. Early specialist referral should be considered for all patients with VA. Particular urgency is recommended in patients with syncope, nonsustained/sustained VA on Holter monitor and SHD on cardiac imaging because of the heightened risk of sudden cardiac death. Comprehensive phenotyping is recommended for most patients with VA, encompassing noninvasive cardiac functional testing, multimodality imaging and genetic testing in select circumstances. Management of idiopathic VA is guided heavily by symptom burden and the presence of ventricular systolic impairment. In SHD, guideline-directed heart failure therapy and device implantation are critical considerations. Whilst commonly used and well-established, antiarrhythmic drugs can be hampered by toxicity and failure of adequate arrhythmia control. Catheter ablation is increasingly being considered a feasible first-line alternative to medical therapy, where outcomes are influenced by disease aetiology and scar burden in SHD. Catheter ablation is associated with reduced arrhythmia recurrence and burden and improved quality of life at follow-up.

May myocardial work predict the risk of cardiomyopathy in patients with premature ventricular complex?

BACKGROUND

An increased premature ventricular complex (PVC) frequency is related to an increased risk of cardiomyopathy. Changes in myocardial work (MW) parameters in patients with PVC may be a predictor of the development of cardiomyopathy.

METHODS

The study included 56 patients with PVC and 50 healthy volunteers as a control group. A comprehensive echocardiographic examination was done. A speckle tracking echocardiography was used to obtain the left ventricle (LV) global longitudinal strain (GLS). A bull's eye plot of the global MW index and the global work efficiency of 17 left ventricle segments with MW component values were generated.

RESULTS

Global work index (GWI), global constructive work (GCW), and global work efficiency (GWE) were significantly lower in the patient group (2377.84 ± 216.52 vs.1818.30 ± 283.73, 2734.00 ± 208.90 vs. 2283.73 ± 321.65, 92.48 ± 2.85 vs. 87.75 ± 3.87, respectively, all p values <0.001). Global wasted work (GWW) was significantly higher in the patient group (216.80 ± 26.86 vs. 302.13 ± 41.81, p < 0.001) Patients were compared according to the origin of PVCs. GWI, GCW, GWE were significantly lower and GWW was significantly higher in patients with PVC originating from the right ventricle or the epicardial region (p < 0.001).

CONCLUSIONS

Compared to healthy individuals, patients with PVC had lower GCW, GWI, GWE values and a higher GWW value than healthy individuals, similar to cardiomyopathy patients. Therefore, the detoriation in MW parameter in patients with PVC may be a predictor of cardiomyopathy development.

Diastolic function evaluation in children with ventricular arrhythmia

Premature ventricular contractions (PVC) are frequently seen in children. We evaluated left ventricular diastolic function in PVC children with normal left ventricular systolic function to detect whether diastolic function disturbances affect physical performance. The study group consisted of 36 PVC children, and the control group comprised 33 healthy volunteers. Echocardiographic diastolic function parameters such as left atrial volume index (LAVI), left atrial strains (AC-R, AC-CT, AC-CD), E wave, E deceleration time (Edt), E/E' ratio, and isovolumic relaxation time (IVRT) were measured. In the cardiopulmonary exercise test (CPET), oxygen uptake (VO_{2 max}) was registered. Evaluation of diastolic function parameters revealed statically significant differences between the patients and controls regarding Edt (176.58 ± 54.8 ms vs. 136.94 ± 27.8 ms, p < 0.01), E/E' (12.6 ± 3.0 vs. 6.7 ± 1.0, p < 0.01), and IVRT (96.6 ± 19.09 ms. vs. 72.86 ± 13.67 ms, p < 0.01). Left atrial function was impaired in the study group compared to controls: LAVI (25.3 ± 8.2 ml/m² vs. 19.2 ± 7.5 ml/m², p < 0.01), AC-CT (34.8 ± 8.6% vs. 44.8 ± 11.8%, p < 0.01), and AC-R-(6.0 ± 4.9% vs. -11.5 ± 3.5%, p < 0.01), respectively. VO2 max in the study group reached 33.1 ± 6.2 ml/min/kg. A statistically significant, moderate, negative correlation between VO2 max and E/E' (r = -0.33, p = 0.02) was found. Left ventricular diastolic function is impaired and deteriorates with the arrhythmia burden increase in PVC children. Ventricular arrhythmia in young individuals may be related to the filling pressure elevation and drive to exercise capacity deterioration.

Successful radiofrequency catheter ablation of idiopathic premature ventricular complexes originating from the outflow tract improves heart failure-related quality of life

BACKGROUND

To investigate the effect of successful RFCA in patients with idiopathic outflow tract PVCs (OT-PVC) on left heart functions, neurohormonal activation, functional status, and heart failure-related quality of life (HFQoL), with an integrated approach.

METHODS

Patients with frequent OT-PVCs, determined by 12-lead surface ECG who underwent radiofrequency catheter ablation (RFCA) with an acute success, were prospectivelly enrolled. Left heart functions were evaluated with the use of transthoracic echocardiography, neurohormonal activation with N-terminal Pro-brain natriuretic peptide (BNP), functional class with New York Heart Association (NYHA) and 6-min walking distance (6MWD), and HFQoL with Minnesota Living with Heart Failure Questionnaire (MLHFQ), at baseline and at 6 months.

RESULTS

A total of 108 patients were included in this study (43 ± 12 years old, 56% male). Majority of the OT-PVCs originated from aortic valve and right ventricle outflow tract (44% and 37%, respectively). Total RF time was 216 ± 87 s. Major complication rate was 0.9%. Left ventricle (LV) ejection fraction increased from 47 ± 8 to 53 ± 6% at 6 months (p < 0.001). Neurohormonal activation was suppressed significantly (104 ± 69 to 83 ± 42, p < 0.001). Functional class improved with %NYHA-I patients increasing from 54 to 89% (p < 0.001) and 6MWD from 293 ± 73 to 335 ± 59 m (p < 0.001). MLHFQ score improved from 32 ± 9 to 23 ± 5 p < 0.001. In multivariable analysis, LV end-systolic diameter (LVESD) and 6MWD were independent predictors of improvement in MLHFQ (for LVESD Uβ: - 0.26, 95%CI [0.44-0.09], p < 0.004 and for 6MWD: 0.04, 95%CI [0.03-0.06], p < 0.001).

CONCLUSIONS

RFCA of OT-PVCs is associated with improved well-being of patients, determined by left heart functions, neurohormonal activation, functional class, and HFQoL.

Cardiopulmonary capacity is reduced in children with ventricular arrhythmia

BACKGROUND

Premature ventricular contractions (PVCs) are frequently seen in children and are considered benign. A substantial group of adolescents with PVCs complain about a broad range of clinical symptoms, including low exertion tolerance.

OBJECTIVE

The purpose of this study was to evaluate prospectively whether ventricular arrhythmia affects physical performance in adolescents with normal left ventricular function, using a cardiopulmonary exercise test (CPET) and evaluating the electrocardiographic (ECG) characteristics of patients with PVCs with regard to exercise capacity.

METHODS

The study group consisted of 49 children with PVCs and normal left ventricular function. The control group consisted of 36 healthy volunteers. Standard ECG, 24-hour Holter ECG, and CPET were performed. PVCs were analyzed for QRS duration, bundle branch block pattern, QRS axis, and coupling interval (CInt). For CPET, heart rate (HR), oxygen uptake (VO_2max), predicted VO_2max, and VO_2max expressed as a percentage of the predicted value (%VO₂) were measured.

RESULTS

In 37 patients (76%), arrhythmia subsided during exercise. Patients achieved lower VO_2max (32.9 ± 6.3 mL/min/kg) than controls (40.4 ± 6.7 mL/min/kg; P <.01). %VO₂ was 71.0 ± 13.7 in patients and 79.3 ± 12.2 in controls (P <.01). Exercise HR at which PVCs subsided correlated with VO_2max (r = 0.3; P = .07). Patients with persisting arrhythmia performed worse than those in whom arrhythmia subsided during exercise (VO_2max, P <.01; %VO_2,P <.01). No correlation between QRS and CInt parameters and VO_2max was observed.

CONCLUSION

Patients with PVCs have lower aerobic capacity than their healthy peers. Further worsening of exercise capacity is present when PVCs are preserved during effort.

Risk factors for the development of premature ventricular complex-induced cardiomyopathy: a systematic review and meta-analysis

Background

Premature ventricular complexes (PVCs) are a potentially reversible cause of heart failure. However, the characteristics of patients most likely to develop impaired left ventricular function are unclear. Hence, the objective of this study is to systematically assess risk factors for the development of PVC-induced cardiomyopathy.

Methods

We performed a structured database search of the scientific literature for studies investigating risk factors for the development of PVC-induced cardiomyopathy (PVC-CM). We investigated the reporting of PVC-CM risk factors (RF) and assessed the comparative association of the different RF using random-effect meta-analysis.

Results

A total of 26 studies (9 prospective and 17 retrospective studies) involving 16,764,641 patients were analyzed (mean age 55 years, 58% women, mean PVC burden 17%). Eleven RF were suitable for quantitative analysis (≥ 3 occurrences in multivariable model assessing a binary change in left ventricular (LV) function). Among these, age (OR 1.02 per increase in the year of age, 95% CI [1.01, 1.02]), the presence of symptoms (OR 0.18, 95% CI [0.05, 0.64]), non-sustained ventricular tachycardias (VT) (OR 3.01, 95% CI [1.39, 6.50]), LV origin (OR 2.20, 95% CI [1.14, 4.23]), epicardial origin (OR 4.72, 95% CI [1.81, 12.34]), the presence of interpolation (OR 4.93, 95% CI [1.66, 14.69]), PVC duration (OR 1.05 per ms increase in QRS-PVC duration [1.004; 1.096]), and PVC burden (OR 1.06, 95% CI [1.04, 1.08]) were all significantly associated with PVC-CM.

Conclusions

In this meta-analysis, the most consistent risk factors for PVC-CM were age, non-sustained VT, LV, epicardial origin, interpolation, and PVC burden, whereas the presence of symptoms significantly reduced the risk. These findings help tailor stringent follow-up of patients presenting with frequent PVCs and normal LV function.

Mechanisms, time course and predictability of premature ventricular contractions cardiomyopathy-an update on its development and resolution

Frequent premature ventricular contractions (PVCs) associated left ventricular systolic dysfunction (LVSD) is a well-known clinical scenario and numerous predictors for cardiomyopathy (CMP) development have been already thoroughly described. It may present as a "pure" form of dissynchrony-induced cardiomyopathy or it may be an aggravating component of a multifactorial structural heart disease. However, the precise risk to develop PVC-induced CMP (which would allow for tailored-patient monitoring and/or early treatment) and the degree of CMP reversibility after PVC suppression/elimination (which may permit appropriate candidate selection for therapy) are unclear. Moreover, there is limited data regarding the time course of CMP development and resolution after arrhythmia suppression. Even less known are the other components of PVC-induced CMP, such as right ventricular (RV) and atrial myopathies. This review targets to synthetize the most recent information in this regard and bring a deeper understanding of this heart failure scenario. The mechanisms, time course (both in experimental models and clinical experiences) and predictors of reverse-remodelling after arrhythmia suppression are described. The novel experience hereby presented may aid everyday clinical practice, promoting a new paradigm involving more complex, multi-level and multi-modality evaluation and possible earlier intervention at least in some patient subsets.

Cardiomyopathy induced by premature ventricular contractions with ventricular escape beats in the compensatory pause: A case report and brief review of the literature

RATIONALE

We reported a case with cardiomyopathy induced by frequent premature ventricular contractions (PVCs) and followed ventricular escape beats (VEBs). PVCs with VEBs in the compensatory pause which induced cardiomyopathy is rarely reported. Also, the case exhibited many characteristics of PVCs which were more likely to induce cardiomyopathy, like the location of origin, the longer coupling interval, and the QRS wave companied with the P wave.

PATIENT CONCERNS

A 53-year-old man with left ventricular (LV) dysfunction presented with palpation, chest distress, and dyspnea for 3 years. Holter revealed a high burden of ventricular rhythm of PVCs and another wide QRS patterns (96,562 total beats with 87,330 wide QRS beats in 24 hours). The LV ejection fraction decreased to 34% and the left ventricle, right and left atria all dilated.

DIAGNOSIS

He was diagnosed with PVC-induced cardiomyopathy.

INTERVENTIONS

The patient experienced intracardiac electrophysiological examination which revealed frequent PVCs followed by VEBs in the compensatory pause. Activation mapping of the PVCS and ablation were performed.

OUTCOMES

PVCs and VEBs disappeared after ablation. The LV ejection fraction increased to 46% at 2 days after the procedure. The diameters of the right and left atria were also significantly reduced.

LESSONS

VEBs may occur during the compensatory pause of PVCs. PVCs with VEBs can lead to a high burden of ventricular rhythm and LV dysfunction. Ablation of the PVCs can also eliminate VEBs and improve the LV function.

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.

Premature Ventricular Contractions Are Presaged by a Mechanically Abnormal Sinus Beat

BACKGROUND

Frequent premature ventricular contractions (PVCs) can lead to cardiomyopathy; it is unclear if there are abnormal myocardial mechanics operative in the PVC and non-PVC beats.

OBJECTIVES

The aim of this study was to investigate regional and global myocardial mechanics, including dyssynchrony, in patients with frequent PVCs.

METHODS

Fifty-six consecutive patients referred for PVC ablation were prospectively studied. During sinus rhythm (SR) and PVC beats, left ventricular (LV) global longitudinal strain (GLS), LV dyssynchrony (measured as the SD of time to peak GLS), and dyssynergy (measured as maximum regional strain minus minimum regional strain at aortic valve closure) were quantified using 2-dimensional strain echocardiography. GLS, dyssynchrony, and dyssynergy were compared in remote SR, pre-PVC SR, PVC, and post-PVC SR beats.

RESULTS

In SR beats remote from the PVC, GLS was -17.3% ± 4%, dyssynchrony was 49 ± 14 ms, and dyssynergy was 22% ± 9%. Myocardial mechanics were significantly abnormal during PVCs compared with remote SR beats (GLS -7.7% ± 3% [P < 0.001], dyssynchrony 115 ± 37 milliseconds [P < 0.001], and dyssynergy 26% ± 10% [P < 0.001]). There were significant mechanical abnormalities in the SR beat preceding the PVC, which demonstrated significantly lower LV strain (pre-PVC SR, -13% ± 4%; P < 0.001) and more dyssynchrony (pre-PVC SR, 63 ± 19 milliseconds; P < 0.001) compared with remote SR beats. Dyssynergy was significantly higher for pre-PVC SR and PVC beats compared with remote SR (pre-PVC SR, 25% ± 8% [P < 0.001]; PVC, 26% ± 10% [P < 0.001]).

CONCLUSIONS

In patients with frequent PVCs, the SR beat preceding the PVC demonstrates significant mechanical abnormalities. This finding suggests that perturbations in cellular physiological processes such as excitation-contraction coupling may underlie the generation of frequent PVCs.

Left Ventricular Dysfunction in Outpatients with Frequent Ventricular Premature Complexes

Frequent ventricular premature complexes (VPCs) and VPC QRS duration are risk factors for left ventricular (LV) dysfunction. To determine which clinical characteristics and electrocardiographic features are associated with LV dysfunction (ejection fraction, &lt;50%) and frequent VPCs, we retrospectively reviewed data from a single-center registry of all patients diagnosed with frequent VPCs at a Korean outpatient clinic.

We identified 412 consecutive outpatients (mean age, 54.7 ± 16.8 yr; 227 women [55.1%]) who were diagnosed with frequent VPCs and had no structural heart disease from January 2010 through December 2017. Available transthoracic echocardiograms and 24-hour Holter monitoring data were evaluated to correlate the occurrence of VPCs and symptoms.

Typical VPC-related symptoms (palpitations or dropped beats) were observed in 251 patients (61.1%). Electrocardiograms revealed VPCs with a left bundle branch block–like morphology in 327 patients (79.5%) and VPCs with an inferior axis in 353 (85.8%). Twenty-six patients (6.3%) were diagnosed with VPC-related LV dysfunction. The mean VPC burden did not differ significantly by LV functional status (11.06% ± 10.13% [normal] vs 14.41% ± 13.30% [impaired]; P=0.211). Patients with impaired LV function were more often men (P=0.027), had no typical VPC-related symptoms (P=0.006), and had significantly longer VPC QRS durations (mean, 157 ms vs 139 ms; P &lt;0.01).

Our findings suggest that male sex, absence of typical VPC-related symptoms, and a VPC QRS duration &gt;157 ms are associated with LV dysfunction in patients with frequent VPCs, findings that may be useful in predicting such dysfunction.

Premature ventricular complexes and development of heart failure in a community-based population

OBJECTIVE

A higher premature ventricular complex (PVC) frequency is associated with incident congestive heart failure (CHF) and death. While certain PVC characteristics may contribute to that risk, the current literature stems from patients in medical settings and is therefore prone to referral bias. This study aims to identify PVC characteristics associated with incident CHF in a community-based setting.

METHODS

The Cardiovascular Health Study is a cohort of community-dwelling individuals who underwent prospective evaluation and follow-up. We analysed 24-hour Holter data to assess PVC characteristics and used multivariable logistic and Cox proportional hazards models to identify predictors of a left ventricular ejection fraction (LVEF) decline and incident CHF, respectively.

RESULTS

Of 871 analysed participants, 316 participants exhibited at least 10 PVCs during the 24-hour recording. For participants with PVCs, the average age was 72±5 years, 41% were women and 93% were white. Over a median follow-up of 11 years, 34% developed CHF. After adjusting for demographics, cardiovascular comorbidities, antiarrhythmic drug use and PVC frequency, a greater heterogeneity of the PVC coupling interval was associated with an increased risk of LVEF decline and incident CHF. Of note, neither PVC duration nor coupling interval duration exhibited a statistically significant relationship with either outcome.

CONCLUSIONS

In this first community-based study to identify Holter-based features of PVCs that are associated with LVEF reduction and incident CHF, the fact that coupling interval heterogeneity was an independent risk factor suggests that the mechanism of PVC generation may influence the risk of heart failure.

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.

Evaluation of five algorithms in predicting the sublocalisation of right ventricular outflow tract arrhythmia (RVOTA) when compared to 3D electroanatomical mapping origin

Purpose

To compare the predictive accuracy of five different algorithms as verified by successful ablation site using 3D electroanatomical non-contact mapping in patients with symptomatic and asymptomatic but high ventricular burden RVOT tachycardias.

Methods

28 Consecutive patients admitted for radiofrequency catheter ablation for symptomatic and asymptomatic, but high ventricular burden idiopathic VPC were recruited for this study. All patients had previous failed or intolerant to beta-blocker and/or at least one class IC anti-arrhythmic agents, and they had normal left ventricular ejection fraction. All patients had documented monomorphic VPC with left bundle branch block morphology and an inferior axis. Concordance of the arrhythmia origin based on ECG algorithm and 3D mapping system site were further evaluated. Of the five algorithms, two algorithms with easy‐applicability and having a memorable design (Dixit and Joshi) and three algorithms with more complex and detailed design (Ito, Zhang, Pytkowski) were selected for comparisons.

Results

Assessment of the diagnostic accuracy showed that each of the five algorithms had only moderate accuracy, and the greatest accuracy was observed in the algorithm proposed by Pytkowski algorithm when assessed by a general cardiologist and Dixit algorithm when evaluated by the electrophysiologist. However, when the algorithms were compared for their accuracy, specificity, sensitivity, no significant differences were found (p = 0.99).

Conclusions

The ECG based algorithms for precise localising RVOTA origin simplify the mapping process, reduce the procedural and fluoroscopic time, and improve clinical outcomes, resulting in greater clinical utility. All the five published 12-lead ECG algorithms for ROTVA differentiation were similar in terms of the diagnostic accuracy, specificity, sensitivity and LRs.

Sarcomeres Morphology and Z-Line Arrangement Disarray Induced by Ventricular Premature Contractions through the Rac2/Cofilin Pathway

The most common ventricular premature contractions (VPCs) originate from the right ventricular outflow tract (RVOT), but the molecular mechanisms of altered cytoskeletons of VPC-induced cardiomyopathy remain unexplored. We created a RVOT bigeminy VPC pig model (n = 6 in each group). Echocardiography was performed. The histopathological alternations in the LV myocardium were analyzed, and next generation sequencing (NGS) and functional enrichment analyses were employed to identify the differentially expressed genes (DEGs) responsible for the histopathological alternations. Finally, a cell silencing model was used to confirm the key regulatory gene and pathway. VPC pigs had increased LV diameters in the 6-month follow-up period. A histological study showed more actin cytoskeleton disorganization and actin accumulation over intercalated disc, Z-line arrangement disarray, increased β-catenin expression, and cardiomyocyte enlargement in the LV myocardium of the VPC pigs compared to the control pigs. The NGS study showed actin cytoskeleton signaling, RhoGDI signaling, and signaling by Rho Family GTPases and ILK Signaling presented z-scores with same activation states. The expressions of Rac family small GTPase 2 (Rac2), the p-cofilin/cofilin ratio, and the F-actin/G-actin ratio were downregulated in the VPC group compared to the control group. Moreover, the intensity and number of actin filaments per cardiomyocyte were significantly decreased by Rac2 siRNA in the cell silencing model. Therefore, the Rac2/cofilin pathway was found to play a crucial role in the sarcomere morphology and Z-line arrangement disarray induced by RVOT bigeminy VPCs.

Post-extrasystolic potentiation as a predictor of premature ventricular contraction-cardiomyopathy in an animal model

AIMS

High premature ventricular contractions (PVCs) burden does not always predict the development of PVC-cardiomyopathy (CM). We sought to evaluate post-extrasystolic potentiation (PESP) of left ventricular ejection fraction (LVEF) to predict the severity of PVC-CM in an animal model.

METHODS AND RESULTS

Right ventricular apical bigeminal PVCs were introduced for 12 weeks in 11 canines to induce PVC-CM. Echocardiograms were performed to obtain LVEF without ectopy (Echo-1) and during PVCs (200 and 350 ms coupling intervals, Echo-2, and Echo-3, respectively), and premature atrial contractions (PACs) (Echo-4) at baseline and after 12 weeks of bigeminal PVCs. PESP was calculated as delta-LVEF between the sinus beat post-ectopy LVEF (Echo-2, -3, and -4, respectively) and LVEF without PVC (Echo-1) at baseline and 12 weeks of high PVC burden. A hyperdynamic LV function (LVEF > 70%) was noted in all animals only with early-coupled PVCs (LVEF at 200 ms: 74.4 ± 6%) at baseline. While PVC PESP at 200 ms had a strong significant correlation with the final 12-week LVEF (R = 0.8, P = 0.003), PVC PESP at 350 ms and PAC PESP had a positive but non-significant correlation (R = 0.53, P = 0.09, and R = 0.29, P = 0.34, respectively). Premature ventricular contraction PESP at 350 ms was significantly higher after PVC-CM had developed (delta-LVEF baseline 2.7 ± 2.9% vs. 12 weeks 18.6 ± 12.3% P < 0.001).

CONCLUSION

Bigeminal early-coupled PVCs cause hyperdynamic left ventricular function in the structurally normal canine heart due to PESP. The degree of PESP at baseline is inversely proportional to the PVC-CM severity at 12 weeks and maybe a predictor of PVC-CM as it may assess the myocardial adaptation reserve to PVCs.

Structural heart disease, not the right ventricular pacing site, determines the QRS duration during right ventricular pacing

Right ventricular (RV) pacing causes changes in the heart's electrical and mechanical activation patterns. The QRS duration is a useful surrogate marker of electrical dyssynchrony; a longer QRS duration during RV pacing indicates poor prognosis. However, the mechanisms underlying a longer QRS duration during RV pacing remain unclear; hence, we investigated factors predicting QRS prolongation during RV pacing. We enrolled 211 patients who underwent catheter ablation for supraventricular tachyarrhythmia and showed no bundle branch block. Three-dimensional mapping for the QRS duration during RV pacing from the RV outflow to RV apex was performed, and differences in the QRS duration were analyzed. The predisposing factors causing QRS > 160 ms during RV apical pacing were also analyzed. The QRS durations at baseline and during RV pacing from the RV outflow and at the RV apex were 85.0 ± 7.5 ms, 163.7 ± 17.1 ms, and 156.2 ± 16.1 ms, respectively. With respect to the QRS duration, there was a significant correlation between RV outflow and RV apical pacing (r = 0.658, p < 0.001). Difference in the QRS duration between the RV outflow and RV apex in each patient was only 12.5 ± 10.4 ms. Logistic multivariable regression analysis identified baseline QRS duration [odds ratio (OR) 1.24, 95% confidence interval (CI) 1.15-1.33, p < 0.01], interventricular septum thickness (OR 1.20, 95% CI 1.02-1.40, p = 0.025), left atrial diameter (OR 1.08, 95% CI 1.01-1.16, p = 0.024), and E/e' (OR 1.23, 95% CI 1.12-1.35, p < 0.01) as significant predictors of QRS prolongation during RV apical pacing. The QRS duration during RV pacing largely depends not on the pacing site, but on the underlying structural heart diseases.

The burden of premature ventricular contractions predicts adverse fetal and neonatal outcomes among pregnant women without structural heart disease: A prospective cohort study

Background

Premature ventricular contractions (PVCs) may increase during pregnancy, however, few studies have evaluated the relationship between PVCs and the pregnant outcomes.

Hypothesis

PVCs may increase the adverse fetal/neonatal outcomes in pregnant women.

Methods

Six thousand one hundred and forty‐eight pregnant women were prospectively enrolled in our center between 2017 and 2019 in the study. The average PVC burden was determined by calculating the number of PVCs in total beats. Those who had a PVC burden >0.5% were divided into two groups based on the presence or absence of adverse fetal or neonatal events. The adverse outcomes were compared between the groups to assess the impact of PVCs on pregnancy.

Results

A total of 103 (1.68%) women with a PVC burden >0.5% were recorded. Among them, 17 adverse events (12 cases) were documented, which was significantly higher than that among women without PVCs (11.65% vs. 2.93%, p < .01). The median PVC burden among pregnant women with PVCs was 2.84% (1.02%–6.1%). Furthermore, compared with that of the women without adverse events, the median PVC burden of women with adverse fetal or neonatal outcomes was significantly higher (9.02% vs. 2.30%, p < .01). Multivariate logistic regression analysis demonstrated that not the LVEF, heart rate and bigeminy, but only the PVC burden was associated with adverse fetal or neonatal outcomes among pregnant women with PVCs (OR: 1.34, 95% CI [1.11–1.61], p < .01).

Conclusions

Frequent PVCs have adverse effects on pregnancy, and the PVC burden might be an important factor associated with adverse fetal and neonatal outcomes among pregnant women with PVCs.

Clinical and translational insights on premature ventricular contractions and PVC-induced cardiomyopathy

The medical community's understanding of the consequences of premature ventricular contractions (PVCs) and PVC-induced cardiomyopathy has been derived mostly from observational and large population-based studies. Due to the difficulty of predicting the development of PVC-cardiomyopathy, the acute and chronic cardiac effects of PVCs and the mechanism of PVC-cardiomyopathy have been derived from pre-clinical studies with large animal models. Recently, these studies have described myocardial substrates that could potentially increase morbidity and mortality in patients with frequent PVCs and PVC-cardiomyopathy. In this paper, we provide an up-to-date comprehensive review of these pre-clinical and clinical studies.

Evaluation of Galectin-3 Plasma Concentration in Adolescents with Ventricular Arrhythmia

Galectin-3 (G3) is a biomarker known as an inflammatory state exponent. The aim of this paper was to analyze the G3 in adolescents with ventricular arrhythmia (VES) in order to evaluate its impact on myocardial tissue preservation. The study group (SG) consisted of 25 VES adolescents. The control group (CG) was 21 healthy children. G3 was assessed in the SG and CG. In the SG electrocardiography, Holter monitoring, echocardiography and CMR were performed. The G3 in SG was 13.45 ± 11.4 ng/mL and in CG 7.2 ± 2.0 ng/mL, p < 0.001. Moderate positive correlation between the G3 and z-score of the left ventricular diameter (r = 0.47, p = 0.041) and moderate negative correlation between the G3 and the left ventricular ejection fraction in cardiac magnetic resonance (CMR EF) (-0.49, p = 0.032) were found. According to the multiple linear regression analysis, CMR EF and VES were independent predictors for G3 elevation. Conclusion: Galectin-3 plasma concentration is elevated and correlates with the chosen left ventricular dysfunction parameters in adolescents suffering from ventricular arrhythmia. Further investigation is necessary to establish if elevated G3 is a useful biomarker for screening young individuals with ventricular arrhythmia who are at risk of structural cardiovascular pathology.

[Management of premature ventricular ectopy in cardiac resynchronization therapy : Treatment strategies for an optimized cardiac resynchronization]

Cardiac resynchronization therapy (CRT) is an integral part in the treatment of chronic heart failure. However, a high degree of biventricular pacing is essential for the effectiveness of this therapy. In addition to atrial fibrillation, premature ventricular contractions (PVC) are a common cause of reduced biventricular stimulation in CRT. In addition to the prognostically unfavorable reduction of biventricular pacing, PVC are generally associated with reduced outcome in the presence of structural heart disease. Options to increase biventricular stimulation percentage by reprogramming the CRT devices are limited in the majority of cases. Due to the mutual relationship between cardiomyopathy and ventricular arrhythmias, adequate heart failure therapy is essential for the reduction of ventricular ectopy. In addition to beta-blocker therapy, specific antiarrhythmic medication is mostly limited to class III antiarrhythmic drugs due to the structural heart disease usually present in CRT patients. Catheter ablation is superior to pharmacological therapy especially in the field of idiopathic PVC, but promising data are also available for catheter ablation of PVC in structural heart disease and CRT nonresponders.

Zero-fluoroscopy catheter ablation of premature ventricular contractions at left coronary cusp near left main coronary artery

The left coronary cusp is the commonest site of origin for coronary cusp PVC. Catheter ablation without fluoroscopy is highly effective, feasible, and safe but it could be related to risks because of proximity to the coronary arteries. The use of ICE integration allowed an improvement in the safety and efficiency of these procedures.

Risk Factors for Left Ventricle Enlargement in Children With Frequent Ventricular Premature Complexes

We aimed to assess the risk factors for left ventricle (LV) enlargement in children with idiopathic frequent ventricular premature complexes (VPC) and discuss the clinical features and treatment strategies. Children diagnosed with idiopathic frequent VPC at Xinhua Hospital affiliated to the Shanghai Jiao Tong University during 2013 to 2019 were retrospectively evaluated. Gender, age, body mass index, weight, number and sources of frequent VPC, and changes in the LV structure were analyzed and compared. A total of 29 patient showed changes in LV enlargement at diagnosis [age 7.3 ± 4.0 years, 8 (24.1%) had symptoms such as syncope, palpitations, fatigue, and dizziness], whereas 220 showed a normal LV structure [age 7.2 ± 4.5 years, 77 (32.3%) with symptoms]. Patients with LV enlargement showed a higher percentage of VPC on Holter recordings (30.2 ± 10.7 versus 9.4 ± 6.9, p < 0.05), higher prevalence of ventricular tachycardia [22 (75.9%) vs 36 (16.4%), p < 0.0001], higher number of couplets [26 (96.7%) vs 132 (60.0%), p = 0.002], higher number of trigeminy [27 (97.8%) vs 133 (83.2%), p < 0.001], higher QRS wave width [80.0 ± 5.9 vs 77.8 ± 6.8, p = 0.021], and higher incidence of right bundle branch block [11 (37.9%) vs 2 (0.9%), p < 0.001]. Multivariate analysis suggested that right bundle branch block (Odds Ratio = 143.9 p <0.001) and VPC burden (>20%) (Odds Ratio = 132.6, p <0.001) were the risk factors for LV enlargement in children with idiopathic frequent VPC. In conclusion, frequent VPC can induce prominent enlargement or LV dysfunction in children. LV enlargement are reversible after catheter ablation or medication.

Impaired left ventricular global longitudinal strain improves with radiofrequency catheter ablation in patients with PVC-induced cardiomyopathy

BACKGROUND

In our study, we aimed to evaluate left ventricular global longitudinal strain (LV-GLS) value in patients with premature ventricular contractions (PVCs) and reduced LV ejection fraction (LVEF) and to determine the effect of radiofrequency catheter ablation (RFA) procedure on LV-GLS.

METHODS

In this cross-sectional study, 150 patients who underwent three-dimensional RFA with the diagnosis of PVCs were included. LV-GLS was measured with strain echocardiography in all patients before RFA and in the sixth-month control. Patients included in the study were grouped as LVEF <50% (Group I) and LVEF ≥50% (Group II) according to baseline LVEF, and patients within Group I were grouped as LVEF <50% (Group A) and LVEF ≥50% (Group B) according to the sixth-month LVEF.

RESULTS

There were 39 patients (26%) with baseline LVEF <50%. In 14 (36%) of these patients, LVEF <50% was observed to continue during the sixth-month controls. Both the baseline and sixth-month LV-GLS values were significantly lower in Group I patients (<0.01). RFA treatment significantly increased both LVEF and LV-GLS (<0.01). It was found that age, N-terminal pro-brain natriuretic peptide, LV diameters, and baseline LVEF were higher, and baseline LV-GLS level was lower in Group A patients (P < .01). Baseline LVEF and LV-GLS values were found to independently determine the patients in Group A (P < .01). In receiver operator characteristic analysis, when the limit value is accepted as 40% for baseline LVEF and 18% for baseline LV-GLS, it can determine Group A with acceptable sensitivity and specificity.

CONCLUSIONS

LV-GLS decreases significantly in patients with reduced LVEF and PVCs. In these patients, RFA treatment significantly increases both LVEF and LV-GLS.

Distinguishing Ventricular Arrhythmias Originating from the Posterior Right Ventricular Outflow Tract, or Near the Right Coronary Cusp or Near the His-Bundle

Differentiation of outflow tract ventricular arrhythmias (OT-VAs) which originate from the posterior right ventricular outflow tract (RVOT), right coronary cusp (RCC) or near the His-bundle are still a challenge until now. This study was aimed to develop a stepwise electrocardiogram (ECG) algorithm to distinguish their locations. Seventy-five consecutive patients with VAs successfully ablated from the posterior RVOT (n = 57), near the His-bundle (n = 5) or RCC (n = 13) were enrolled in our study. Measurements with highest diagnostic performance were chosen to develop a diagnostic algorithm. Of all these ECG measurements, the R-wave amplitude in lead I and V2S/V3R index showed the best diagnostic performance to discriminate these anatomical sites. The optimal ECG discriminators were different combination of lead I and V2S/V3R index as follows: the posterior RVOT, Lead I R-wave amplitude <0.65 mV and V2S/V3R index>1.5 (96.2% sensitivity, 69.6% specificity); the near the His-bundle, lead I R-wave amplitude ≥0.65 mV and V2S/V3R index>1.5 (100% sensitivity, 70% specificity); RCC, lead I R-wave amplitude<0.65 mV and V2S/V3R index ≤1.5 (52.9% sensitivity, 93.1% specificity). Sequential algorithmic application of these criteria resulted in an overall accuracy of 83% in predicting site of OT-VA origin. A predominantly positive R-wave in lead I is seen in OT-VAs originated near the His-bundle. A stepwise ECG algorithm of combination with R-wave amplitude in lead I and V2S/V3R index could localize the origins of OT-VAs from the posterior RVOT, near the His-bundle and the RCC with a high accuracy.

Electrocardiographic characteristics of idiopathic ventricular arrhythmias based on anatomy

Idiopathic ventricular arrhythmia (IVA) is a term used to describe a spectrum of ventricular arrhythmia without structural heart disease (SHD). IVAs contain premature ventricular contractions (PVCs), nonsustained monomorphic ventricular tachycardia (VT), and sustained VT. Electrocardiography is a fundamental and important tool to diagnose and localize IVAs. More detailed, IVAs originating from different origins exhibit characterized ECGs due to their specific anatomic backgrounds. As catheter ablation becomes widely used to eliminate these arrhythmias, its high success rate is based on accurate localization of their origins. Therefore, these ECG characteristics show great importance for precise localization of their origins and subsequently successful ablation. This review aims to sum up ECG characteristics of IVAs based on anatomy and give brief introduction of mechanisms and treatment of IVAs.

Electrocardiographic features of the presence of occult myocardial disease in patients with VPD-induced cardiomyopathy

Background

Frequent ventricular premature depolarizations (VPDs) can cause reversible cardiomyopathy (CMP). However, many patients maintain a normal left ventricular (LV) function with a high VPD burden. The electrocardiographic characteristics of VPD‐induced CMP have not been elucidated.

Methods

One hundred and eighty (91 men, age; 51 ± 15 years) patients with frequent idiopathic VPDs (>10% VPDs/day or >10 000 VPDs/day) were studied. All patients underwent successful ablation and were then divided into two groups according to the echocardiographic findings before and after the ablation procedure.

Results

Group A (n = 139) had a normal LV function with VPD frequencies, and Group B (n = 41) had reversible LV dysfunction after ablation. The VPD QRS duration (QRSd) was wider in patients with CMP (Group A vs Group B; 137.2 ± 12.0 milliseconds vs 159.7 ± 5.3 milliseconds, P < .001). VPDs with a terminal QRS delay marked by a notch followed by a discrete lower amplitude signal after the peak R wave in any precordial lead were identified. The incidence of terminal signals was higher in the CMP group (Group A vs Group B; 2.1% vs 53.6%, P < .001).

Conclusions

The wider VPD QRSd and terminal QRS delay in patients with VPD‐induced CMP suggest subclinical cell‐to‐cell conduction abnormalities as a potential factor predisposing VPD‐induced CMP.