Utility of new FDG-PET/CT guidelines for diagnosing cardiac sarcoidosis in patients with implanted cardiac pacemakers for atrioventricular block.

Diagnosing cardiac sarcoidosis (CS), especially in isolated cases, is challenging, particularly due to the limitations of endomyocardial biopsy, leading to potential undiagnosed cases in pacemaker-implanted patients. This study aims to provide real world findings to support new guideline for CS using 18F-fluoro-deoxyglucose positron-emission tomography computed tomography (FDG-PET/CT) which give a definite diagnosis of isolated CS (iCS) without histological findings. We examined consecutive patients with cardiac pacemakers for atrioventricular block (AV-b) attending our outpatient pacemaker clinic. The patients underwent periodical follow-up echocardiography and were divided into two groups according to echocardiographic findings: those with suspected CS and those without suspected CS. Patients suspected of having nonischemic cardiomyopathy underwent FDG-PET/CT for CS diagnosis. We investigated the utility of the new guideline for CS using FDG-PET/CT. Among the 272 patients enrolled, 97 patients were implanted with cardiac pacemakers for AV-b. Twenty-two patients were suspected of having CS during a median observation period of 5.4 years after pacemaker implantation. Of these, one did not consent, and nine of 21 cases (43%) were diagnosed with definite CS according to the new guidelines. Five of these nine patients were diagnosed with iCS using FDG-PET/CT. The number of patients diagnosed with definite CS using the new guidelines tended to be approximately 2.3 times that of the conventional criteria (p = 0.074). Three of the nine patients underwent steroid treatment. The composite outcome, comprising all-cause death, heart failure hospitalization, and a substantial reduction in left ventricular ejection fraction, were significantly lower in patients receiving steroid treatment compared to those without steroid treatment (p = 0.048). The utilization of FDG-PET/CT in accordance with the new guidelines facilitates the diagnosis of CS, including iCS, resulting in approximately 2.3 times as many diagnoses of CS compared to the conventional criteria. This guideline has the potential to support the early identification of iCS and may contribute to enhancing patient clinical outcomes.

Impact of general anesthesia on ablation catheter stability during pulmonary vein isolation based on a novel measurement approach.

Catheter ablation for atrial fibrillation (AF) during pulmonary vein isolation (PVI) is performed under general anesthesia (GA) or conscious sedation (CS). GA during PVI may improve treatment outcomes by improving catheter stability. However, the magnitude of GA-derived catheter stability compared with that of CS is unclear. We directly assessed catheter movement and determined the impact of GA compared with that of CS on ablation catheter stability during PVI. Patients who underwent initial ablation using the EnSite Precision™ mapping system were recruited and divided into two groups (GA and CS groups). The two groups were compared for ablation catheter stability during PVI based on the distance traveled by the catheter distal tip per second, clinical periprocedural characteristics, and periprocedural complications. Among 69 consecutively admitted patients, data of 30 patients (17 in the GA group and 13 in the CS group) and the distance traveled per second by the catheter on 148,976 points/patient were evaluated. The GA group had a significantly smaller catheter tip travel distance than the CS group (0.92 [0.82‒1.16] vs. 1.25 [1.14‒1.38], p = 0.01). Therefore, GA during PVI for AF provides greater catheter stability than CS and will contribute to more accessible and safer PVI procedures.