The prognostic value of dispersion of repolarization in stress cardiomyopathy.

INTRODUCTION: Although abnormalities of ventricular repolarization are a hallmark of SC, their clinical impact on management remains to be determined. This study sought to evaluate the prognostic value of dispersion of repolarization in stress cardiomyopathy (SC) with regards to major cardiac events (MCE), recovery time, and recurrence. METHODS: This study analyzed data from258 patients with SC, from January 2009 to January 2018. Standard 12 lead ECG recordings during the acute, subacute, and recovery phases were collected for each eligible patient. Logistic regression was used to identify independent predictors of MCE, a composite of 30 day all-cause mortality, cardiogenic shock, life-threatening ventricular arrhythmias, and stroke. RESULTS: Among the 101 eligible patients (80.2% females, mean age 45.8 ± 11.5 years) in the study cohort, MCE occurred in 16 patients (15.8%). Cox regression analysis identified two independent predictors of MCE: increased ΔQT dispersion ≥ 40 ms (HR 1.31, 95% CI 1.05-9.77, p = 0.029) and increased Δnegative T wave amplitude dispersion ≤ -2.0 mV (HR 1.25, 95% CI 1.11-11.93, p = 0.018) during the subacute phase. The final regression model had good accuracy (sensitivity 81.3%, specificity 96.5%) and discriminative power (AUC 0.89, 95% CI 0.83-0.95). Kaplan-Meier analysis revealed that there was increasing MCE in patients with zero, one, or two predictors (log rank p < 0.001). In addition, patients with increased dispersion also had a significantly longer time to achieve complete recovery (21.4 ± 6.8 vs. 8.5 ± 4.3 days, p = 0.012) and a higher incidence of recurrence (31.3% vs. 2.4%, p = 0.011) of SC. CONCLUSION: Evaluation of dynamic changes of dispersion of repolarization is a simple bed-side tool with high predictive accuracy for prognostication of short term adverse outcomes, delayed recovery, and recurrence in patients with SC.

A novel prediction model for risk stratification in patients with a type 1 Brugada ECG pattern.

BACKGROUND: Risk stratification in Brugada syndrome remains a controversial and unresolved clinical problem, especially in asymptomatic patients with a type 1 ECG pattern. The purpose of this study is to derive and validate a prediction model based on clinical and ECG parameters to effectively identify patients with a type 1 ECG pattern who are at high risk of major arrhythmic events (MAE) during follow-up. METHODS: This study analysed data from 103 consecutive patients with Brugada Type 1 ECG pattern and no history of previous cardiac arrest. The prediction model was derived using logistic regression with MAE as the primary outcome, and patient demographic and electrocardiographic parameters as potential predictor variables. The model was externally validated in an independent cohort of 42 patients. RESULTS: The final model (Brugada Risk Stratification [BRS] score) consisted of 4 independent predictors (1 point each) of MAE during follow-up (median 85.3 months): spontaneous type 1 pattern, QRS fragments in inferior leads≥3,S wave upslope duration ratio ≥ 0.8, and T peak - T end ≥ 100 ms. The BRS score (AUC = 0.95,95% CI 0.0.92-0.98) stratifies patients with a type 1 ECG pattern into low (BRS score ≤ 2) and high (BRS score ≥ 3) risk classes, with a class specific risk of MAE of 0-1.1% and 92.3-100% across the derivation and validation cohorts, respectively. CONCLUSIONS: The BRS score is a simple bed-side tool with high predictive accuracy, for risk stratification of patients with a Brugada Type 1 ECG pattern. Prospective validation of the prediction model is necessary before this score can be implemented in clinical practice.

Primary transcatheter closure of post-myocardial infarction ventricular septal rupture using amplatzer atrial septal occlusion device: A study from tertiary care in South India.

OBJECTIVE: The study investigated effectiveness of transcatheter closure of post-myocardial infarction (MI) ventricular septal rupture (VSR) using atrial septal device (ASD) occluder in a cohort of patients admitted at our institute. METHOD: This was a retrospective, observational and single center study, which included patients who were treated with transcatheter closure for post-MI VSR at our tertiary care center between May 2000 and August 2014 depending upon inclusion and exclusion criteria. Primary outcome was all-cause mortality at 30-days follow-up. The MELD-XI (Model for End Stage Liver Disease) score was used as a predictor for poor outcome in these patients. RESULTS: A total of 21 patients (mean age 66.4±5.9years) were included in the study. Study cohort predominantly included male patients (n=15; 71.4%) and patients with single vessel disease (n=15; 71.4%). Revascularization of the culprit lesion, before VSR closure, was attempted in 6 patients. Except one patient (treated with Cera® occluder), all patients were treated with Amplatzer® ASD occluders. Average diameter of VSR was 20.8±6.9mm. Diameter of the device used in the study ranged from 10mm to 30mm. Residual defect was detected in 13 patients (62%). All-cause mortality at 30-day follow-up was observed in 9 (42.9%) patients. Time to VSR closure, diameter of VSR, and serum creatinine levels were significantly related to the 30-day mortality. MELD-XI score was found to be strongly associated with increased risk of mortality. CONCLUSION: Primary transcatheter VSR closure using ASD occluders is a feasible approach which can provide reasonable survival outcomes along with equitable mortality rates.

Familial atrioventricular nodal re-entrant tachycardia: A case seriers and a systematic review.

Multiple reports of familial clustering suggest that genetic factors may contribute in the pathogenesis of atrioventricular nodal re-entrant tachycardia (AVNRT). We report three cases of AVNRT in a father and his two sons along with a review of literature of other similar cases. Electrophysiological studies induced typical AVNRT, which was successfully eliminated by radiofrequency ablation in all of them. Of the 22 reported cases, 96% had typical (slow-fast) variant of AVNRT. The predominant pattern of inheritance appears to be autosomal dominant, though other patterns may exist. Further research is needed to understand the genetic influence of AVNRT and its pathophysiology.

Derivation and Validation of a Novel Prediction Model to Identify Low-Risk Patients With Acute Pulmonary Embolism.

Accurate identification of low-risk patients with acute pulmonary embolism (PE) who may be eligible for outpatient treatment or early discharge can have substantial cost-saving benefit. The purpose of this study was to derive and validate a prediction model to effectively identify patients with PE at low risk of short-term mortality, right ventricular dysfunction, and other nonfatal outcomes. This study analyzed data from 400 consecutive patients with acute PE. We derived and internally validated our prediction rule based on clinically significant variables that are routinely available at initial examination and that were categorized and weighted using coefficients in the multivariate logistic regression. The model was externally validated in an independent cohort of 82 patients. The final model (HOPPE score) consisted of 5 categorized patient variables (1, 2, or 3 points, respectively): systolic blood pressure (>120, 100 to 119, <99 mm Hg), diastolic blood pressure (>80, 65 to 79, <64 mm Hg), heart rate (<80, 81 to 100, >101 beats/min), arterial partial pressure of oxygen (>80, 60 to 79, <59 mm Hg), and modified electrocardiographic score (<2, 2 to 4, >4). The 30-day mortality rates were 0% in low risk (0 to 6 points), 7.5% to 8.5% in intermediate risk (7 to 10), and 18.2% to 18.8% in high-risk patients (≥11) across the derivation and validation cohorts. In comparison with the previously validated PESI score, the HOPPE score had a higher discriminatory power (area under the curve 0.74 vs 0.85, p = 0.033) and significantly improved both the discrimination (integrated discrimination improvement, p = 0.002) and reclassification (net reclassification improvement, p = 0.003) of the model for short-term mortality. In conclusion, the HOPPE score accurately identifies acute patients with PE at low risk of short-term mortality, right ventricular dysfunction, and other nonfatal outcomes. Prospective validation of the prediction model is necessary before implementation in clinical practice.

The Utility of Exercise Testing in Risk Stratification of Asymptomatic Patients With Type 1 Brugada Pattern.

INTRODUCTION: Risk stratification of asymptomatic patients with a Brugada type 1 ECG pattern remains an unresolved clinical conundrum. In contrast to provocative pharmacological testing in Brugada syndrome, there is limited data on the role of exercise stress testing as a risk stratification modality. The objective of this study was to evaluate the utility of exercise testing in asymptomatic patients with type 1 Brugada pattern to prognosticate major arrhythmic events (MAE) during follow-up. METHODS AND RESULTS: Treadmill exercise testing was conducted for 75 asymptomatic patients with type 1 Brugada pattern and for 88 healthy control subjects. The clinical end point of MAE was defined as the occurrence of sudden cardiac death (SCD) or resuscitated ventricular fibrillation (VF). During a follow-up of 77.9 ± 28.9 months, eight MAE occurred (five VF and three SCD). Multivariate Cox regression analysis showed that the following were independent predictors of MAE in asymptomatic patients with a type 1 Brugada pattern: increase in S wave upslope duration ratio >30% at peak exercise (HR 1.35, 95% CI 1.08-10.97, P = 0.023), augmentation of J point elevation in lead aVR >2 mm in late recovery (HR 1.88, 95% 1.21-15.67, P = 0.011), and delayed HR recovery (HR 1.14, 95% CI 1.06-18.22, P = 0.042). A high-risk cohort was identified by the final step-wise regression model with good accuracy (specificity = 98.4%, sensitivity = 62.5%) and discriminative power (AUC = 0.93, 95% CI 0.89-0.96, P = 0.002). Kaplan-Meier analysis revealed increasing MAE in subjects with one, two, or three predictors, respectively (log rank P < 0.001). CONCLUSIONS: Exercise testing in asymptomatic patients with type 1 Brugada pattern aids in identification of high-risk patients and provides a unique window of opportunity for early intervention.

Coronary Stent Infection Successfully Diagnosed Using 18F-Flurodeoxyglucose Positron Emission Tomography Computed Tomography.

Infection of coronary stents is extremely rare. We report a case of a 60-year-old gentleman with recurrent fever after acute stent occlusion and reintervention. A coronary angiogram showed an occluded stented segment and the blood cultures were positive for infection. The presence of inflammation in the stented region was confirmed using 18F-flurodeoxyglucose positron emission tomography computed tomography. The patient underwent surgery and the diagnosis was proven by examination of the surgical material. This article highlights the need to have a high index of suspicion of stent infection, and the use of 18F-flurodeoxyglucose positron emission tomography computed tomography along with coronary angiogram in aiding the diagnosis.