Speckle tracking strain and ECG heterogeneity correlate in transcatheter aortic valve replacement-induced left bundle branch blocks and right ventricular paced rhythms.

OBJECTIVE: Transcatheter aortic valve replacement (TAVR) complications include left bundle branch block (LBBB) and right ventricular paced rhythm (RVP). We hypothesised that changes in electrocardiographic heterogeneity would correlate better with speckle tracking strain measures than with left ventricular ejection fraction (LVEF) on transthoracic echocardiogram (TTE) among patients with TAVR-induced conduction abnormalities. METHODS: We reviewed medical records of 446 consecutive patients who underwent TAVR at our institution. Of the 238 patients with 12-lead electrocardiograms (ECGs) that met our inclusion criteria, 58 had pre-TAVR and post-TAVR TTEs adequate for strain assessment. We compared patients who did not have an LBBB or RVP pre-TAVR and post-TAVR (controls, n=11) with patients who developed LBBBs (n=11) and who required RVPs (n=10) post-TAVR. In our study population (n=32, 41% female, mean age 85.8 years), we evaluated QRS complex duration, R-wave heterogeneity (RWH), T-wave heterogeneity (TWH), LVEF, global longitudinal strain (GLS) and mechanical dispersion (MD). RESULTS: TAVR-induced changes on ECG did not correlate with LVEF. TAVR-induced changes in MD and QRS complex duration correlated among all patients (r=0.4, p=0.04). GLS and RWH correlated among RVP patients (r=0.7, p=0.00003). MD and TWH correlated among LBBB patients (r=0.7, p=0.00004). CONCLUSIONS: In this convenience sample of patients with TAVR-induced conduction abnormalities, RWH and TWH correlated with strain measures but not with LVEF. Strain measures, RWH and TWH may offer additional insights for pre-TAVR evaluation and post-TAVR clinical management.

The Impact of Basal Septal Hypertrophy on Outcomes after Transcatheter Aortic Valve Replacement.

BACKGROUND: The role of basal septal hypertrophy (BSH) on preprocedural transthoracic echocardiography in transcatheter aortic valve replacement (TAVR) is unknown. METHODS: Medical charts and preprocedural transthoracic echocardiograms of 378 patients who underwent TAVR were examined. The association between BSH and the primary composite outcome of valve pop-out, recapture, embolization, aborted procedure, conversion to open procedure, new conduction disturbance, or need for permanent pacemaker ≤30 days after TAVR was evaluated. Patients with preexisting pacemakers were excluded. Sensitivity analyses were performed varying the definition of BSH. RESULTS: Of 296 TAVR patients (78.3%) with interpretable images, 55 (18.6%) had BSH at a median of 40 days (interquartile range, 19-62 days) before TAVR. Age and sex were similar among those with and without BSH. BSH patients received postdilation more frequently (BSH+ vs BSH-: 41.8% vs 29.9%, P = .04). A total of 50 individuals (16.9%) received pacemakers within 30 days, and 128 (43.2%) developed conduction disturbances (with left bundle branch block most common), without differences between groups. BSH was unrelated to the primary outcome on multivariate analysis (adjusted odds ratio BSH+ vs BSH-, 0.94; 95% CI, 0.42-2.11; P = .88). CONCLUSIONS: In this convenience sample of TAVR recipients at a large academic medical center, patients with BSH were more likely to receive postdilation. BSH was not associated with procedural or conduction outcomes after TAVR in patients without preexisting pacemakers.

Temporal Associations Between Smoking and Cardiovascular Disease, 1971 to 2006 (from the Framingham Heart Study).

Smoking has consistently been related to cardiovascular risk. Public health efforts have yielded reduced smoking prevalence and gains in cardiovascular disease (CVD) prevention. We hypothesized that the contribution of tobacco to CVD risk would be attenuated over prospective decades (1971 to 2006) in a community-based cohort. We evaluated 5,041 Framingham Heart Study Offspring Cohort participants (mean age 36.1 years, 52% women) without prevalent CVD. We collected prospective data on smoking status, relevant CVD risk factors, and incident CVD events across prospective decades. We used multivariable-adjusted, Cox proportional hazard models to measure the effect of smoking on incident CVD over 3 prospective 12-year follow-up periods. Our results demonstrated a consistent twofold increased risk of CVD in men who smoke compared with nonsmokers for each 12-year time period spanning from 1971 to 2006. Women who smoked had a 1.5-fold increased CVD risk. Smoking remains an important risk factor despite substantial improvements in the prevention and treatment of CVD. Significant, contemporary improvements in CVD prevention-such as gains in hypertension and cholesterol treatment-have not attenuated the strong and persistent associations between smoking and CVD observed here. In conclusion, our results highlight the importance of continued public health efforts to address smoking as a modifiable exposure that strongly contributes toward CVD risk.

Assessment of reproducibility--automated and digital caliper ECG measurement in the Framingham Heart Study.

BACKGROUND: Digitized electrocardiography permits the rapid, automated quantification of electrocardiograms (ECGs) for analysis. Community- and population-based studies have increasingly integrated such data. Assessing the reproducibility of automated ECG measures with manual measures is a critical step in preparation for using automated measures for research purposes. We recently established an ECG repository of digitally recorded ECGs for the Framingham Heart Study and we sought to assess the reproducibility of automated and manual measures. METHODS: We selected 185 digitally recorded ECGs from routine visits of Framingham Heart Study participants spanning from 1986 to 2012. We selected the following ECG measures for their relevance to clinical and epidemiologic research: P wave duration, P wave amplitude, and PR interval in lead II; QRS duration and R wave amplitude in lead V6; and QT interval in lead V5. We obtained automated values for each waveform, and used a digital caliper for manual measurements. Digital caliper measurements were repeated in a subset (n=81) of the samples for intrarater assessment. RESULTS: We calculated the intraclass correlation coefficient (ICC) values for the interrater and intrarater assessments. P wave duration had the lowest interrater ICC (r=0.46) and lowest intrarater ICC (r=0.57). R wave amplitude had the highest interrater and intrarater ICC (r=0.98) indicating excellent reproducibility. The remaining measures had interrater and intrarater ICCs of r≥0.81. CONCLUSIONS: The interrater reproducibility findings for P wave amplitude, PR interval, QT interval, QRS duration, and R wave amplitude were excellent. In contrast, the reproducibility of P wave duration was more modest. These findings indicate high reproducibility of most automated and manual ECG measurements.

Renal sympathetic denervation for the treatment of systemic hypertension.

Systemic hypertension is a common cardiovascular problem that often cannot be fully treated with existing nonpharmacologic and pharmacologic measures. A catheter-based strategy which denervates the renal afferent and efferent autonomic nervous system has been developed for the treatment of drug-resistant hypertension. In early clinical trials, this procedure was shown to be both feasible and safe in reducing blood pressure in patients with uncontrolled hypertension receiving treatment with a minimum of 3 antihypertensive drugs. In addition, this procedure has been associated with decreased renin secretion, preservation of renal function, improved glucose tolerance, and a reduction in left ventricular hypertrophy. The long-term effects of this procedure (beyond 3 years) still need to be determined. A large 530-patient sham-controlled trial is now in progress.

Moyamoya disease: a summary.

Moyamoya, meaning a "hazy puff of smoke" in Japanese, is a chronic, occlusive cerebrovascular disease involving bilateral stenosis or occlusion of the terminal portion of the internal carotid arteries (ICAs) and/or the proximal portions of the anterior cerebral arteries and middle cerebral arteries (MCAs). The Ministry of Health and Welfare of Japan has defined 4 types of moyamoya disease (MMD): ischemic, hemorrhagic, epileptic, and "other." The ischemic type has been shown to predominate in childhood, while the hemorrhagic type is more often observed in the adult population. The highest prevalence of MMD is found in Japan, with a higher female to male ratio. Studies have shown a possible genetic association of MMD linked to chromosome 17 in Japanese cases as well as in cases found in other demographics. During autopsy, intracerebral hematoma is found and most commonly serves as the major cause of death in patients with MMD. Moyamoya vessels at the base of the brain are composed of medium-sized or small muscular arteries emanating from the circle of Willis, mainly the intracranial portions of ICAs, anterior choroidal arteries, and posterior cerebral arteries, forming complex channels that connect with distal positions of the MCAs. Off of these channels are small tortuous and dilated vessels that penetrate into the base of the brain at the site of the thalamoperforate and lenticulostriate arteries. On angiography, there is the characteristic stenosis or occlusion bilaterally at the terminal portion of the ICAs as well as the moyamoya vessels at the base of the brain. Six angiographic stages have been described, from Stage 1, which reveals a narrowing of the carotid forks, to Stage 6, in which the moyamoya vessels disappear and collateral circulation is produced solely from the external carotid arteries. Cases with milder symptoms are usually treated conservatively; however, more severe symptomatic cases are treated using revascularization procedures. Surgical treatments are divided into 3 types: direct, indirect, and combined/other methods. Direct bypass includes superficial temporal artery-MCA bypass or use of other graft types. Indirect procedures bring in circulation to the intracranial regions by introducing newly developed vasculature from newly approximated tissues. These procedures may not be enough to prevent further ischemia; therefore, a combination of direct and indirect procedures is more suitable. This article will give a review of the epidemiology, natural history, pathology, pathophysiology, and diagnostic criteria, including imaging, and briefly describe the surgical treatment of MMD.

BMPR1a signaling determines numbers of oligodendrocytes and calbindin-expressing interneurons in the cortex.

Progenitor cells that express the transcription factor olig1 generate several neural cell types including oligodendrocytes and GABAergic interneurons in the dorsal cortex. The fate of these progenitor cells is regulated by a number of signals including bone morphogenetic proteins (BMPs) secreted in the dorsal forebrain. BMPs signal by binding to heteromeric serine-threonine kinase receptors formed by type I (BMPR1a, BMPR1b, Alk2) and type II (BMPRII) subunits. To determine the specific role of the BMPR1a subunit in lineage commitment by olig1-expressing cells, we used a cre/loxP genetic approach to ablate BMPR1a in these cells while leaving signaling from other subunits intact. There was a reduction in numbers of immature oligodendrocytes in the BMPR1a-null mutant brains at birth. However, by postnatal day 20, the BMPR1a-null mice had a significant increase in the number of mature and immature oligodendrocytes compared with wild-type littermates. There was also an increase in the proportion of calbindin-positive interneurons in the dorsomedial cortex of BMPR1a-null mice at birth without any change in the number of parvalbumin- or calretinin-positive cells. These effects were attributable, at least in part, to a decrease in the length of the cell cycle in subventricular zone progenitor cells. Thus, our findings indicate that BMPR1a mediates the suppressive effects of BMP signaling on oligodendrocyte lineage commitment and on the specification of calbindin-positive interneurons in the dorsomedial cortex.