Long-term monitoring of arrhythmias in cardiac sarcoidosis

Introduction

Screening for cardiac sarcoidosis (CS) is recommended since it can manifest with ventricular arrhythmias (VA), atrioventricular conduction block (AVB) and sudden cardiac death (SCD). However, risk stratification for SCD is challenging, in particular in patients without overt cardiac symptoms.

Purpose

This study reports the practice-based risk stratification for SCD and the incidence of arrhythmias and mortality in CS patients by long-term monitoring of arrhythmias.

Methods

A retrospective, single center cohort study was performed in 537 patients with sarcoidosis screened for cardiac involvement with cardiac MRI and fluorodeoxyglucose PET in an hospital, a Dutch tertiary referral center. CS was diagnosed in 115 of 537 patients (21%), complete follow up was available in 108 patients (94%). After risk assessment for SCD (figure 1) an ICD was implanted in 16 high-risk patients. Within the92 low-risk patients, 80 had an internal loop recorder (ILR) implanted and 12 patients received no device. Chart review was performed to assess the occurrence of VA, AVB, death, ICD therapy and device related complications.

Results

During a mean follow-up of 31±15 months, 9 out of 80 ILR patients (11.3%) received an ICD of whom 7 (8.8%) based on recorded arrhythmias (VA in 5 and AVB in 2 patients).

Five out of the total 25 ICD patients (20%) experienced sustained VA successfully treated with anti-tachycardia pacing in 2 (8%) and terminated spontaneously in all other patients. Two ICD patients experienced a mild pocket infection, treated with antibiotics. Two deaths occurred in the low-risk patients: 1 non-cardiac death and 1 SCD due to asystole.

Conclusion

The practice-based risk stratification supported an ICD implantation in up to 5% of sarcoidosis patients screened for CS. Sustained VA occurred in 20% of ICD patients.Early detection of important arrhythmias with an ILR can optimize risk assessment for SCD in CS.

Practise-based risk stratification

Funding Acknowledgement

Type of funding source: None

Effect of rewarming speed during hypothermic cardiopulmonary bypass on cerebral pressure-flow relation

BACKGROUND

Cerebral blood flow is less dependent on arterial blood pressure during hypothermic cardiopulmonary bypass (CPB) compared to warm CPB. Fast rewarming has a more pronounced effect on cognitive performance in the elderly and causes an increased arterio-jugular oxygen content difference. We studied the effect of rewarming and rewarming speed on cerebral pressure-flow relation in adult patients undergoing elective coronary artery bypass surgery with mild hypothermic CPB.

METHODS

Fifty patients were randomly assigned to either a slow rewarming strategy (0.24 degrees C/min) or a fast rewarming strategy (0.5 degrees C/min). Cerebral pressure-flow relation was assessed by a transcranial Doppler derived index for cerebral pressure-flow relation (Pressure-flow Index, PFI). The effect of rewarming speed on cerebral pressure-flow relation was assessed by comparing the absolute PFI value after rewarming between the two treatment groups.

RESULTS

The mean PFI decreased significantly from 0.73 (standard deviation: 0.28) before rewarming to 0.54 (0.35) after rewarming in the slow rewarming group and from 0.63 (0.29) to 0.48 (0.30) in the fast rewarming group. Absolute PFI after rewarming was not significantly different (mean PFI difference = 0.06; 95% CI = - 0.13; 0.26) between both rewarming strategies.

CONCLUSION

Rewarming from mild hypothermic CPB might result in pressure-dependent cerebral blood flow velocity but rewarming speed did not aggravate the effect of rewarming on pressure-flow dependency.