Mitral Annulus Calcification and Cardiac Conduction Disturbances: A DANCAVAS Sub-study.

BACKGROUND: Due to its location very close to the bundle of His, mitral annulus calcification (MAC) might be associated with the development of atrioventricular (AV) conduction disturbances. This study assessed the association between MAC and AV conduction disturbances identified by cardiac implantable electronic device (CIED) use and electrocardiographic parameters. The association between MAC and traditional cardiovascular risk factors was also assessed. METHODS: This cross-sectional study analyzed 14,771 participants, predominantly men aged 60-75 years, from the population-based Danish Cardiovascular Screening trial. Traditional cardiovascular risk factors were obtained. Using cardiac non-contrast computed tomography imaging, MAC scores were measured using the Agatston method and divided into absent versus present and score categories. CIED implantation data were obtained from the Danish Pacemaker and Implantable Cardioverter Defibrillator Register. A 12-lead electrocardiogram was available for 2,107 participants. Associations between MAC scores and AV conduction disturbances were assessed using multivariate regression analyses. RESULTS: MAC was present in 22.4% of the study subjects. Participants with pacemakers for an AV conduction disturbance had significantly higher MAC scores (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.01-1.23) than participants without a CIED, whereas participants with a CIED for other reasons did not. Prolonged QRS-interval was significantly associated with the presence of MAC (OR, 1.45; 95% CI, 1.04-2.04), whereas prolonged PQ-interval was not. Female sex and most traditional cardiovascular risk factors were significantly associated with high MAC scores. CONCLUSIONS: MAC was associated with AV conduction disturbances, which could improve our understanding of the development of AV conduction disturbances.

Aortic valve calcification among elderly males from the general population, associated echocardiographic findings, and clinical implications.

AIMS: Aortic valve calcification (AVC) detected by non-contrast computed tomography (NCCT) associates with morbidity and mortality in patients with aortic valve stenosis. However, the importance of AVC in the general population is sparsely evaluated. We intend to describe the associations between AVC score on NCCT and echocardiographic findings as left atrial (LA) dilatation, left ventricular (LV) hypertrophy, aortic valve area (AVA), peak velocity, mean gradient, and aortic valve replacement (AVR) in a population with AVC scores ≥300 AU. METHODS AND RESULTS: Of 10 471 males aged 65-74 years from the Danish Cardiovascular Screening trial (DANCAVAS), participants with AVC score ≥300 AU were invited for transthoracic echocardiography and 828 (77%) of 1075 accepted the invitation. AVC scores were categorized (300-599, 600-799, 800-1199, and ≥1200 AU). AVR was obtained from registries. AVC was significantly associated with a steady increase in LA dilation (10.5%, 16.3%, 15.8%, 19.6%, P = 0.031), LV hypertrophy (3.9%, 6.6%, 8.9%, 10.1%, P = 0.021), peak velocity (1.7, 1.9, 2.1, 2.8 m/s, P = 0001), mean gradient (6, 8, 11, 19 mmHg, P = 0.0001), and a decrease in AVA (2.0, 1.9, 1.7, 1.3 cm2, P = 0.0001). The area under the curve was 0.79, 0.93, and 0.92 for AVA ≤1.5 cm2, peak velocity ≥3.0 m/s, and mean gradient ≥20 mmHg, respectively, and the associated optimal AVC score thresholds were 734, 1081, and 1019 AU. AVC > 1200 AU was associated with AVR (P < 0.0001). CONCLUSION: Among males from the background population, increasing AVC scores were associated with LA dilatation, LV hypertrophy, AVA, peak aortic velocity, mean aortic gradient, and AVR.

Prognostic importance of left atrial size measured by non-contrast cardiac computed tomography - A DANCAVAS study.

BACKGROUND: Enlargement of left atrium (LA) is a valuable marker of cardiovascular events, and LA size is readily available while performing non-contrast cardiac computed tomography (NCCT) for preventive purposes. We aimed to evaluate the predictive value of a single LA area from NCCT in a population-based cohort. METHOD: Mainly men aged 60-75 years from DANCAVAS were included. Traditional risk factors were recorded, and an NCCT scan performed at baseline. Coronary artery calcifications (CAC) score and the largest LA area were measured. LA was indexed to body surface area and categorised into four groups. Data on incident atrial fibrillation (AF), thromboembolic events, heart failure (HF) and death were obtained from Danish national registries. RESULTS: In total, 14,557 individuals were eligible, excluding those without LA measurement (N = 232) and with heart valve replacement (N = 197). Known AF or HF were respectively excluded from follow-up. Median follow-up time was 2.1 to 3.4 years. In total, 304 developed AF, 149 had thromboembolism, 129 developed HF and 482 died. In adjusted analysis, LA enlargement was associated with AF (HR (95% CI): large 1.99 (1.46-2.71) and very large LA 3.77 (2.31-6.14)) and HF (large 2.40 (1.50-3.85) and very large LA 6.54 (4.07-10.51)). A very large LA significantly increased mortality (HR: 2.01 (1.44-2.82)), and was associated with a two-fold increased risk of thromboembolism; however, not significantly in adjusted analysis (p = 0.09). CONCLUSION: We demonstrated that determination of LA area from NCCT was an important predictor of AF, HF and death. This knowledge could inform current risk assessment beyond CAC score.