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.

Influence of electromagnetic interference on implanted cardiac arrhythmia devices in and around a magnetically levitated linear motor car.

This study was designed to determine the susceptibility of implanted cardiac arrhythmia devices to electromagnetic interference in and around a magnetically levitated linear motor car [High-Speed Surface Transport (HSST)]. During the study, cardiac devices were connected to a phantom model that had similar characteristics to the human body. Three pacemakers from three manufacturers and one implantable cardioverter-defibrillator (ICD) were evaluated in and around the magnetically levitated vehicle. The system is based on a normal conductive system levitated by the attractive force of magnets and propelled by a linear induction motor without wheels. The magnetic field strength at 40 cm from the vehicle in the nonlevitating state was 0.12 mT and that during levitation was 0.20 mT. The magnetic and electric field strengths on a seat close to the variable voltage/variable frequency inverter while the vehicle was moving and at rest were 0.13 mT, 2.95 V/m and 0.04 mT, 0.36 V/m, respectively. Data recorded on a seat close to the reactor while the vehicle was moving and at rest were 0.09 mT, 2.45 V/m and 0.05 mT, 1.46 V/m, respectively. Measured magnetic and electric field strengths both inside and outside the linear motor car were too low to result in device inactivation. No sensing, pacing, or arrhythmic interactions were noted with any pacemaker or ICD programmed in either bipolar and unipolar configurations. In conclusion, our data suggest that a permanent programming change or a device failure is unlikely to occur and that the linear motor car system is probably safe for patients with one of the four implanted cardiac arrhythmia devices used in this study under the conditions tested.

[Improvement of mental health and the quality of life after catheter ablation for paroxysmal supraventricular tachycardia].

PURPOSE: The aims of this study were to observe change in subjective symptoms, quality of life (QOL) and mental health condition after catheter ablation (CA) for paroxysmal supraventricular tachycardia (PSVT) and to assess patient evaluation of the treatment. METHODS: The questionnaire was sent to 103 patients (86 with the Wolff-Parkinson-White (WPW) syndrome and 27 with atriovetricular nodal reentrant tachycardia (AVNRT)), who had received CA from February 1995 to January 1999. The question encompassed the condition of the patient, his or her evaluation of CA treatment, and a self-rating depression scale (SDS) together with social and subjective as well as non-specific physical points. We scored for improvement of QOL and SDS. Finally, from 82 patients who participated complete responses to the questionnaire were received from 59 (72.0%). The patients (50.5 +/- 15.8 years old, WPW syndrome; 41, AVNRT; 18) almost all (98.3%) RESULTS: gave a positive evaluation of CA. Over half (54.2%) no longer needed hospital consultation for any reason while three-quarters (76.3%) were free of life limitations. The complete cure rate from physicians was 100%. However, subjective symptoms of arrhythmia attack remained in 20.3% of the cases. Social and physical QOL were significantly improved after CA (social: < 0.05, physical: < 0.01) and the SDS score decreased significantly (< 0.05). 1. Self-awareness frequency of tachycardia attack, frequency of going to hospital and life CONCLUSION: limitations of PSVT patients decreased after CA. 2. QOL (social and physical QOL) and mental health condition significantly improved after CA. 3. Almost all patients (98.3%) gave a positive evaluation of CA. 4. Healthcare professionals should be aware that not only drug therapy, but also CA is effective for improvement of mental health and the QOL of patients with PSVT.