Association of nailfold capillaroscopic features with cardiac block and arrhythmias due to systemic sclerosis-related primary heart involvement

Impaired microvascular function has been implicated as a complication affecting multi­ple organs in systemic sclerosis (SSc). We investigated the correlation between microvascular damage on nailfold video capillaroscopy (NVC) and cardiac arrhythmias or conduction blocks in patients with primary heart involvement (pHI). One hundred ten patients with SSc underwent an NVC study. Thirty-one patients with arrhythmias or conduction blocks were included in the study group. No patients in this group had pulmonary arterial hypertension, systemic hypertension, or ischemic heart disease. Seventy-nine patients with no arrhythmia or block were included in the control group. Qualitative, quantitative, and semi-quantitative capillaroscopic parameters were compared between the 2 groups. In the qualitative NVC analysis the odds ratio (OR) for the early pattern in groups of patients with and without a cardiac outcome was 0.93 (95% CI: 0.35–2.45; p = 0.89). The ORs for the active and late patterns in the 2 groups of patients were 0.92 (95% CI: 0.37–2.30, p = 0.86) and 1.07 (95% CI: 0.52–2.19; p = 0.84), respectively. Semi-quantitative assessment in 6 NVC parame­ters showed that the mean score for capillary density was higher in the outcome group than in the non-outcome group (mean ±standard deviation: 2.19 ±0.910 vs. 1.72 ±1.120; p = 0.04). Capillary disorganization also showed a higher score in patients with cardiac involvement than in those without (1.00 ±0.01 vs. 0.95 ±0.221, p = 0.001). Low capillary density in NVC was associated with sensitivity (Se) of 96.7%, and specificity (Sp) of 18.9%. Disorganized capillaries showed Se of 96.7% and Sp of 5%. However, no significant differences were observed in enlarged capillaries, giant capillaries, microhemorrhages, or ramifications. Lower capillary density and greater disorganization are associated with arrhythmias and conduction blocks in SSc-PHI. The quantitative capillaroscopic parameters were comparable between patients with arrhythmias due to SSc-PHI and those in the non-outcome group. A detailed semi-quantitative capillaroscopic assessment is recommended in scleroderma patients.