Flecainide challenge test: Predictors of unmasking of type 1 Brugada ECG pattern among those with non-type 1 Brugada ECG pattern

AbstractBackgroundMany subjects in community have non-type 1 Brugada pattern ECG with atypical symptoms, relevance of which is not clear. Provocative tests to unmask type 1 Brugada pattern in these patients would help in diagnosing Brugada Syndrome. However sensitivity and specificity of provocating drugs are variable.MethodsWe studied 29 patients referred to our institute with clinical presentation suggestive but not diagnostic of Brugada or with non-Type 1 Brugada pattern ECG. Flecainide Challenge Test (FCT) was done in these patients (IV Flecainide test in 4 patients and Oral Flecainide in 25 patients). Resting 12-lead ECG with standard precordial leads and ECG with precordial leads placed 1 Intercostal space above were performed after flecainide administration every 5 min for first 30 min and every 30 min thereafter until ECG became normal or upto 6 h. The positivity was defined as inducible Type 1 Brugada pattern in atleast 2 right sided leads.ResultMedian age was 35(range = 5–65) years. In 16 (55%) patients the Type 1 Brugada pattern was unmasked. There were no episodes of major AV block, atrial or ventricular tachyarrhythmia. Three groups were considered for analysis: Group 1(n = 9) – FCT Positive among patients with non-type 1 Brugada ECG pattern, Group 2(n = 4) – FCT Negative among the patients with non-type 1 Brugada ECG pattern, and Group 3(n = 7) – FCT Positive among patients with no spontaneous Brugada ECG pattern. Binary logistic regression analysis found that family h/o SCD was predictive of FCT positivity in Group 1 (Odd’s ratio 21, 95% Confidence interval 1.04 to 698.83, p = 0.004).ConclusionOral flecainide is useful and safe for unmasking of Type I Brugada pattern. In our study, among the many variables studied, family history of sudden cardiac death was the only predictor of flecainide test positivity among those with non-Type 1 Brugada pattern

A case of ‘Masquerading’ bundle branch block: A forgotten concept

‘Masquerading’ bundle branch block (right bundle branch block in the precordial leads with left bundle branch block in frontal leads and left axis deviation) is seen most commonly with coronary artery disease and hypertension. No definite explanation is available so far for these changes. We are presenting a case of rare congenital intranuclear inclusion myopathy with congestive heart failure and ‘Masquerading’ bundle branch block in ECG

Differential diagnosis of vascular structures in relation to upper ascending aorta: The retro-aortic innominate vein

The retroaortic course of left innominate vein is a rare entity which can be misinterpreted during echocardiography for other abnormal vascular structures under the arch of aorta. We report the case of a 2 month old infant where the suprasternal window showed 2 vascular structures beneath the aortic arch, one of which was traced to be a retroaortic innominate vein

Acquired fontan paradox in isolated right ventricular cardiomyopathy

A 44-year-old woman presented with features of congestive heart failure. Echocardiography revealed severe right ventricular dysfunction along with passive minimally pulsatile pulmonary blood flow suggesting very high systemic venous pressures. This was confirmed with cardiac catheterization in which the pressures of superior vena cava and inferior vena cava (19 mmHg) were higher than the pulmonary artery pressures (17 mmHg). Elevation of systemic venous pressures above the pulmonary venous pressures, Fontan paradox, to drive the forward flow, is a specific feature of artificially created cavopulmonary shunts. Late stage of isolated right ventricular cardiomyopathy resulted in the spontaneous evolution of Fontan circulation with a nonfunctional right ventricle in this patient

Prevalence of electrocardiographic changes in patients with acute aneurysmal subarachnoid hemorrhage and their relationship with outcome

Background Electrocardiographic (ECG) alterations occurring after subarachnoid hemorrhage (SAH) have been described frequently, but the prognostic significance of these changes has not been well characterized. Aim and Objectives To report the prevalence and patterns of ECG alterations in patients with acute aneurysmal SAH and to study the relationship between ECG alterations and the neurological outcome, if any. Materials and Methods Records of consecutive patients admitted to the neurosurgical intensive care unit of the SCTIMST, Trivandrum between January 1999 and January 2011 with acute aneurysmal SAH were retrospectively analyzed. Results Of the 321 patients with SAH, 190 (59.2%) had abnormal ECGs. Repolarization abnormalities were the most common, with T wave inversion in the anterolateral leads occurring in 155 (48.3%) patients. By univariate analysis, female sex, Glasgow Coma Score (GCS) at admission of I, ST segment depression or T inversion in anterolateral leads, prolonged corrected QT interval, and sinus bradycardia were associated with increased risk of death. By multivariate analysis, only GCS and WFNS grade independently predicted mortality and none of the ECG changes predicted the same. Presence of tall T waves in anterior leads, T inversion in anterolateral leads, sinus bradycardia, and WFNS grade >1 were independently associated with GCS <15 and poor outcome at discharge. Conclusions In patients with acute aneurysmal SAH, repolarization abnormalities are the commonest ECG alterations. ECG alterations do not independently predict death, but independently predict poor discharge neurological status