Bjarne Martens Nes

Aims Left atrial (LA) and ventricular (LV) remodelling is thought to be balanced in healthy individuals, and the LA end-systolic volume (LAV) to LV end-diastolic volume (LVEDV) ratio (LA:LV) could help discriminate between pathological and physiological LA enlargement. We aimed to assess LA:LV and its associations with age, sex, and cardiovascular risk factors HbA1C, body mass index (BMI), systolic blood pressure, and peak oxygen uptake (VO2peak). The association to measures of LV diastolic function and filling pressures were compared with LAV and LA reservoir strain. Methods and results Cardiopulmonary exercise testing and measurement of risk factors 10 years apart and echocardiography at follow-up was performed in 1348 healthy adults [52% women, mean (SD) age 59 (12) years] prospectively included in a large population study. All risk factors were significantly associated with LA:LV in univariate analyses, while BMI and VO2peak were significantly associated with LA:LV in adjusted models. A higher LA:LV was associated with increased odds ratio (OR) of diastolic dysfunction [OR (95% CI) 2.6 (2.1, 3.3)]. Measures of LV filling pressures were more closely associated with LA:LV than LAV and LA reservoir strain, but LA reservoir strain was more closely related to some diastolic function measures. In individuals with LAV > 34 mL/m2, the LA:LV explained 29% of variance in VO2peak (P < 0.001). Conclusion A higher LA:LV was associated with, and may improve, assessment of diastolic dysfunction and filling pressures. The LA:LV differentiates VO2peak in individuals with enlarged LAV and may have a role in evaluating whether LA enlargement reflects pathology.

OBJECTIVES Aortic valve stenosis (AVS) shares many risk factors with coronary disease, the latter being strongly and inversely associated with physical activity (PA) and cardiorespiratory fitness (CRF). However, the relationship between PA, CRF and AVS needs to be established. We explored whether PA habits and estimated CRF affect the risk of developing AVS demanding aortic valve replacement (AVR) and how these factors affect postoperative mortality. METHODS Participants from the second and third waves of Trøndelag Health Study were cross-linked with a local heart surgery registry and the Norwegian Cause of Death Registry. Estimated CRF was calculated through a developed algorithm based on clinical and self-reported data. Fine-Gray competing risk analyses were used to investigate how PA habits and estimated CRF were associated with the risk of AVR across CRF quintiles, PA groups and per 1-metabolic equivalent task (MET) (3.5 ml/min/kg). RESULTS In a study population of 57 214 participants, we found a 15% [95% confidence interval (CI) 1–27] reduced risk of AVR per 1-MET estimated CRF increment. Those in the highest CRF quintile had a 56% (95% CI 14–77) lower risk of surgery compared to the lowest quintile. Analyses on PA groups did not show significant results. Finally, we found a 37% (95% CI 17–53) lower risk of postoperative mortality per 1-MET increased estimated CRF. CONCLUSIONS Our findings indicate a strong and inverse relationship between estimated CRF and incidence of AVR due to AVS. Higher estimated CRF was associated with lower mortality after surgery.