Right Bundle-Branch Block Ventricular Tachycardias

Abstract

Background-Identifying the septal versus lateral site of origin of ventricular tachycardia (VT) with a right bundle-branch block (RBBB)-type pattern and an R-S ratio Ͼ1 in lead V 1 is difficult with the 12-lead ECG, especially in patients with prior apical infarction. Methods and Results-We prospectively evaluated 58 patients with VT. Sixteen patients had apical infarcts (group 1), 29 had nonapical infarcts (group 2), and 13 had no heart disease (group 3). QRS complex onset to activation at the right ventricular apex (stim-RVA) was measured during left ventricular (LV) apical septal and lateral pacing, and 47 RBBB-type VTs (QRS-RVA) were localized to the septal or lateral apex by using entrainment techniques. Pacing and VT site of origin were confirmed by electroanatomic mapping. The stim-RVA time was 59Ϯ16 ms for septal versus 187Ϯ24 ms for lateral sites in group 1, PϽ0.001; 70Ϯ14 ms for septal versus 169Ϯ19 ms for lateral sites in group 2, PϽ0.001; and 42Ϯ15 ms for septal versus 86Ϯ16 ms for lateral sites in group 3, PϽ0.005. The QRS-RVA time was 50Ϯ13 ms for apical septal VTs versus 178Ϯ21 ms for lateral VTs in group 1, PϽ0.001; 71Ϯ17 ms for apical septal versus 157Ϯ20 ms for lateral VTs in group 2, PϽ0.001; and 32Ϯ12 ms for septal versus 71Ϯ16 ms for lateral VTs in group 3, PϽ0.01. Conclusions-The QRS-RVA differs for the VT site of origin from the LV septal versus lateral apex. These data prove useful in rapidly regionalizing the VT site of origin with a V 1 R-S ratio Ͼ1, particularly in instances of an apical infarct, where surface ECG distinctions are less identifiable.

Hypertriglyceridemia and Ischemic Stroke

“…In contrast to the findings of the above studies, other trials have reported a positive association between hypertriglyceridemia and IS [43,44,45,46] (table 3). In the Blood Lipids and First-Ever Ischemic Stroke/Transient Ischemic Attack in the Bezafibrate Infarction Prevention (BIP) registry [43], a large prospective trial of 11,177 patients with known underlying CHD, fasting hypertriglyceridemia was found to be an independent risk factor for the development of first-ever IS or TIA.…”

“…No subanalysis of IS patients alone was conducted. The meta-analysis of prospective studies by the Asia-Pacific Cohort Studies Collaboration (APCSC) included 96,224 individuals, with 796,671 person-years of follow-up [44]. In 90% of the participants the triglyceride levels were measured after fasting.…”

Very low density lipoprotein cholesterol associates with coronary artery calcification in type 2 diabetes beyond circulating levels of triglycerides

“…1–4 Many prospective epidemiological studies suggest that while elevated serum TGs are associated with coronary heart disease (CHD), this relationship is attenuated after adjusting for high-density lipoprotein cholesterol (HDL-C) and LDL-C. 5 However, such adjustments may actually obscure true causal relationships particularly given our incomplete understanding of the biological pathways in metabolism of TGRL. 6 Recent genomic studies provide additional evidence for a causal and independent association between loci related to TG pathways and CVD.…”

Atherogenic index of plasma in highly active antiretroviral therapy-naïve patients with human immunodeficiency virus infection in Southeast Nigeria

“…[7] Recent meta-analyses of prospective studies indicate that elevated triglycerides (TGs) are also an independent risk factor for coronary heart disease (CHD). [89]…”