Key Points
- The study aims to analyze capillary morphology in patients with coronary artery disease and idiopathic dilated cardiomyopathy.
- Performed electron microscopic morphometry on endomyocardial biopsy samples from 32 patients with angina, dilated cardiomyopathy, and controls.
- Quantitatively assessed cross-sectional areas of capillaries and myocyte ratios among different patient groups.
- In patients with dilated cardiomyopathy, mean cross-sectional areas of capillaries were significantly larger than controls (45.3 +/- 15.1 vs 22.7 +/- 8.3 micron^2, p < 0.001).
- Patients with small vessel disease had a reduced capillary-to-myocyte ratio (0.33 +/- 0.08, p < 0.001) and absence of capillaries less than 15 micron^2.
- Mild increases in fibrous content were observed in both patient groups, with significant differences from controls (DCM 16.3 +/- 3.3% vs controls 5.0 +/- 2.4%, p < 0.001).
Structured PICO
PPopulation32 patients: 10 with angina, normal epicardial coronary arteries, and evidence for small vessel disease (SVD); 12 with idiopathic dilated cardiomyopathy (DCM); and 10 with normal hearts (controls).
CComparator10 patients with normal hearts (controls)
OOutcomeMorphology of capillaries (ratio of microvessels to myocytes, cross-sectional areas of capillaries and lumen) and fibrous content of the myocardium assessed via electron microscopic morphometry of right ventricular biopsy samplessurrogate
Patients with dilated cardiomyopathy exhibit enlarged capillaries, whereas those with small vessel disease and angina show a relative lack of capillaries and lumen narrowing, highlighting distinct microvascular pathophysiologies.