Myocardial strain analysis by 4D-speckle tracking echocardiography for prediction of coronary artery disease severity in patients with stable angina pectoris.

OBJECTIVE: We sought to evaluate the myocardial strain by four-dimensional speckle-tracking echocardiography (4D-STE) in patients with stable angina pectoris (SAP) to determine the severity of coronary artery disease (CAD) based on the Gensini score. METHODS: The present study comprised of 150 patients with SAP. Patients with history of SAP, normal left ventricular ejection fraction, and without regional wall motion abnormalities (RWMA) were scheduled for elective coronary angiography. Based on Gensini score, there were two groups: non-critical stenosis group [Gensini score (0-19), n = 117] and critical stenosis group [Gensini score ≥20, n = 33]. Correlation between Gensini score and 4D-STE strain parameters were investigated. RESULTS: Out of 150 patients, critical stenosis group had significantly depressed values of all 4D-STE strain parameters than non-critical stenosis group (p < 0.001), except global radial strain (GRS) parameter. Significant positive correlation was found between Gensini score and 4D global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS) with Spearman's correlation coefficient (ρ) as 0.626, 0.548, and 0.631, respectively (p < 0.001), whereas significant negative correlation was found between Gensini score and GRS (ρ = -0.433, p < 0.001). A 4D GLS value of ≥ -17 had 84.9% sensitivity and 97.4% specificity, GAS ≥ -31 (90.9% sensitivity, 78.6% specificity), GCS ≥ -17 (69.7% sensitivity, 92.3% specificity), and GRS <47 (sensitivity 72.7%, specificity 76.1%) to detect critical CAD described by Gensini score ≥20. CONCLUSION: The 4D-STE can aid in the assessment of severe CAD stenosis with good sensitivity and specificity in the patients with SAP without RWMA on traditional echocardiography.

Correlation of endothelial dysfunction measured by flow-mediated vasodilatation to severity of coronary artery disease.

OBJECTIVES: Brachial artery ultrasound imaging during reactive hyperemia is widely used tool for quantifying endothelium dependent vasomotion. Angiodefender device is used for non invasive determination of percentage flow mediated vasodilation (FMD). An attempt is made to study whether endothelial dysfunction determined by FMD of brachial artery predicts the presence or absence of coronary artery disease and its correlation with the severity of coronary artery disease. METHODS: One hundred six patients admitted between May 2014 and April 2015 who were posted for coronary angiography diagnosed to have chronic stable angina on clinical basis and/or by exercise stress test, for evaluation of coronary artery disease were submitted to standard clinical evaluation, calculation of percentage FMD by Angiodefender device. Statistical significance of difference of categorical variables was tested using Fisher's exact test. Sensitivity, specificity, positive predictive value and negative predictive value of FMD were studied. RESULTS: There was no correlation between number of risk factors and percentage of FMD. Significantly higher proportion of cases with less FMD had higher prevalence of coronary artery disease and vice-versa. Significantly higher proportion of cases with positive stress test had less percentage of FMD and vice-versa. Significantly higher proportion of cases with less percentage of FMD and positive stress test had higher prevalence of obstructive coronary artery disease and vice-versa. Specificity was 100% when percentage of FMD was ≤10. CONCLUSIONS: FMD an inexpensive and non-invasive test provides information regarding extent and severity of coronary artery disease.

Determinants of implantable defibrillator discharges in high-risk patients with hypertrophic cardiomyopathy.

OBJECTIVES: To identify the determinants of appropriate and inappropriate implantable cardioverter-defibrillator (ICD) discharges in patients with hypertrophic cardiomyopathy (HCM). DESIGN: Retrospective cohort study. SETTING: ICD clinic at an academic hospital. PATIENTS: 61 patients with HCM who received ICDs for the primary or secondary prevention of sudden cardiac death (SCD). OUTCOME MEASURES: (a) Analysis of appropriate and inappropriate ICD discharges; (b) predictors of ICD discharges. RESULTS: Mean (SD) age at ICD insertion was 46 (18) years (range 10-79). Follow-up time was 40 (27) months (range 7-151). Eight patients experienced an appropriate discharge, occurring 24.5 (13.6) months after ICD insertion. Appropriate ICD intervention was more common in the secondary (36%) than the primary (8%) prevention group (p = 0.02). Inappropriate ICD discharges occurred in 20 (33%) patients. Multivariate Cox regression analysis identified two significant predictors of inappropriate ICD discharges: (a) age <30 years at the time of ICD insertion (hazard ratio (HR) = 3.0 (95% CI 1.1 to 8.0; p = 0.03) and (b) history of atrial fibrillation (HR = 3.1 (95% CI 1.2 to 8.1; p = 0.02). CONCLUSIONS: ICDs are effective in the prevention of SCD in HCM. However, there is a high incidence of inappropriate ICD discharges.

Percutaneous treatment of dissection of the ascending aorta occurring as a complication during coronary angioplasty of a saphenous vein bypass graft.

Aortocoronary dissection can occur as a complication of angioplasty of native coronary arteries. This case report is of aortic dissection occurring as a complication of percutaneous coronary intervention of proximal anastomoses of a saphenous vein bypass graft. The aortic dissection that had progressed retrogradely into the ascending aorta was treated percutaneously by stenting in the saphenous vein graft with a membrane-covered stent.

Spontaneous dissection of the left main coronary artery.

Spontaneous coronary artery dissection remains a rare but important cause of acute coronary syndromes. Presentation depends on the extent of the dissection, the vessels involved and the rate of its development, and can encompass the entire spectrum of coronary syndromes, with some patients being asymptomatic and others presenting with angina, non-ST segment elevation myocardial infarction, ST-elevation myocardial infarction and sudden cardiac death. The authors describe a 33-year-old pregnant woman who presented with a non-ST segment elevation myocardial infarction secondary to a spontaneous dissection of the left main coronary artery.

Inappropriate therapy from a defibrillator complicating transcoronary ablation of septal hypertrophy in a patient with hypertrophic obstructive cardiomyopathy.

This case report describes a patient with obstructive hypertrophic cardiomyopathy who received therapy inappropriately from his implanted defibrillator, subsequent to transcoronary alcohol ablation for septal hypertrophy (TASH). Widening of the intracardiac electrogram postablation resulted in "double counting" of the intrinsic ventricular electrogram by the device and inappropriate tachycardia detection.

Radiofrequency catheter ablation of a posteroseptal accessory pathway along the morphologic tricuspid valve in a patient with congenitally corrected transposition of the great arteries and complete atrioventricular block.

We report a patient with Congenitally Corrected Transposition of the Great Arteries, complete atrioventricular block and a posteroseptal accessory pathway across the morphologic tricuspid valve. Ablation of the accessory pathway was performed for her symptomatic palpitations.

Thromboembolism: a rare complication of cardiac hydatidosis.

A cardiac hydatid cyst is rare. We report a case of cardiac hydatid cyst localized in the atria which was diagnosed by two-dimensional echocardiography following a thromboembolic stroke. Surgical resection of the cyst was performed and histopathologic examination confirmed the diagnosis.

Intracardiac echocardiography guided radiofrequency catheter ablation of the slow pathway in atrioventricular nodal reentrant tachycardia.

BACKGROUND: ICE has demonstrated its utility in imaging right atrial structures but its utility in slow pathway (SP) ablation has not been documented in a randomized trial. METHODS: The feasibility of using ICE as a imaging modality to identify the effective site of SP ablation was done in part one of the study comprising 10 patients of typical AVNRT. Subsequently, a prospective randomized study was done comparing the conventional (group A) and ICE guided (group B) ablation of the SP. Each group had 20 patients of typical AVNRT. Ablation in the conventional arm was guided by intracardiac electrograms and fluoroscopy. Group B patients underwent SP ablation guided primarily by ICE imaging; fluoroscopy was used mainly for initial placement of catheters. RESULTS: Reliable & stable ICE images were obtained in all patients. Part I of the study showed that RF pulses given when the ablation catheter was seen to cross the atrioventricular muscular septum (AVMS), always resulted in junctional rhythm. In Group B, RF pulse was delivered only when the ablation catheter was at the AVMS making an obtuse angle with the image of the His-bundle catheter. Consistent junctional rhythm and abolition of SP resulted at this site. Compared to group A, patients in group B required fewer pulses (mean 1.4 +/- 0.6 vs. 4.4 +/- 3.0; p < 0.05, median 1 vs. 5; p < 0.01), achieved a higher temperature (56 +/- 4 degrees C vs. 50 +/- 6 degrees C) and had more frequent junctional rhythm (100% vs. 70%) during RF pulse. CONCLUSIONS: A critical portion of SP exists adjacent to Tricuspid valve overlying the AVMS. ICE imaging consistently and reliably localizes this site and RF applications here result in interruption of antegrade SP conduction.

Split atrial electrograms recorded during dual chamber pacing.

Split atrial electrograms (AEGs), as a measure of intraatrial conduction delay, have been previously identified during electrophysiological studies and as such, may be related to the development of atrial tachyarrhythmias. This article reports the finding of split AEGs observed in two patients with implanted dual chamber pacemakers. The event marker and the surface electrogram identified these AEGs by using and interpreting the intracardiac AEG derived from the atrial pacing lead.