Impact of nocturnal blood pressure dipping on recurrence of atrial fibrillation after pulmonary vein isolation.

Lack of the typical nocturnal blood pressure (BP) fall, i.e non-dipper, has been known as a cardiovascular risk. However, the influence of non-dipper on atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) has been unclear. We investigated the clinical impact of non-dipping as evaluated by 24-hour ambulatory BP monitoring on the long-term outcome of AF recurrence post-PVI in 76 AF patients with a history of increased BP. The PVI procedure was successful in all 76 patients (mean age, 66±9years; antihypertensive medication, 89%; non-paroxysmal AF, 24%). Twenty patients had AF recurrence during a median follow-up of 1138 days. There was no difference in BP levels between the AF recurrence and non-recurrence groups (average 24 h systolic BP:126 ± 17 vs.125 ± 14 mmHg; P = 0.84). On the other hand, the patients with non-dipper had a higher AF recurrence than those with dipper (38.9% vs.15.0%; P = 0.018). In Cox hazard analysis adjusted by age, non-paroxysmal AF and average 24-hr systolic BP level, the non-dipper was an independent predictor of AF recurrence (HR 2.78 [95%CI:1.05-7.34], P = 0.039). Non-dipper patients had a larger left atrial (LA) volume index than the dipper patients (45.9 ± 17.3 vs.38.3 ± 10.2 ml/m2, P = 0.037). Among the 58 patients who underwent high-density voltage mapping in LA, 11 patients had a low-voltage area (LVA) defined as an area with a bipolar voltage < 0.5 mV. However, there was no association of LVA with non-dipper or dipper (22.2% vs.16.1%, P = 0.555). Non-dipper is an independent predictor of AF recurrence post-PVI. Management of abnormal diurnal BP variation post-PVI may be important.

Comparison of heart rate and cardiac output of VVI pacemaker settings in patients with atrial fibrillation with bradycardia.

Background: While most VVI pacemakers in bradycardic patients are set to a low limit of 60/min, the optimal lower limit rate for VVI pacemakers in atrial fibrillation has not been established. Although an increase in heart rate within the normal range in the setting of a VVI pacemaker might be expected to lead to an increase in cardiac output with the shortening of the diastolic time, the changes in cardiac output at different pacemaker settings have not been fully clarified. Methods: We included 11 patients with bradycardic atrial fibrillation who had VVI pacemakers implanted. Stroke volume was measured using the electrical cardiometry method (AESCULONⓇ mini; Osypka Medical) without pacing and at ventricular pacings of 60, 70, 80, and 90/min. Results: Stroke volume decreased stepwise at ventricular pacing rates of 60, 70, 80, and 90/min (63.6 ± 11.2, 61.9 ± 10.6, 59.3 ± 12.2, and 57.5 ± 12.2 mL, p < .001), but cardiac output increased (3.81 ± 0.67, 4.33 ± 0.74, 4.74 ± 0.97, and 5.17 ± 1.09 L/min, p < .001). The rate of increase in cardiac output at a pacing rate of 70/min compared to 60/min correlated with left ventricular end-systolic volume (r = 0.711, p = .014). Conclusions: Cardiac output increased at a pacing rate of 70 compared to 60 in bradycardic atrial fibrillation patients, and the rate of increase in cardiac output was greater in those with larger left ventricular end-systolic volume.

Impact of unipolar voltage criteria for left atrial posterior wall on atrial fibrillation recurrence after pulmonary vein isolation.

INTRODUCTION: Beyond pulmonary vein isolation (PVI), additional therapeutic strategies for atrial fibrillation (AF) have not been established. Remodeling of the left atrium (LA) could impact AF recurrence post-PVI. We investigated the impact of unipolar voltage (UV) criteria for the LA posterior wall (LA-PW) on AF recurrence post-PVI. METHODS: We reviewed the cases of 106 AF patients (mean age 63.8 years, nonparoxysmal AF: 59%) who underwent extensive encircling PVI by radiofrequency ablation guided by a 3-dimension mapping system, investigating the impact on AF recurrence of the UV criteria of the LA. RESULTS: Out of all patients, 26 patients had AF recurrence during post-PVI follow-up [median 603 days]. They showed a higher percentage of nonparoxysmal AF (80.8 vs. 52.5%, p = .011), longer AF duration (2.9 ± 2.7 vs. 1.0 ± 1.7 years, p = .002), and larger area size of UV < 2.0 mV in LA-PW (2.8 ± 1.8 vs. 1.0 ± 1.5 cm2 , p < .001) than those without recurrence. Cox Hazard analysis for AF recurrence adjusted by age, gender, AF duration, body mass index and left atrial volume index revealed that an area size over 2.0 cm2 of UV < 2.0 mV in LA-PW (HR 6.9 [95% CI:1.3-35.5], p = .021) posed independent risks for AF recurrence post-PVI. The atrial arrhythmia-free survival rate was higher in those with no area of UV < 3.0 mV in LA-PW compared to those with a sizable area (>2.0 cm2 ) of UV < 3.0 mV and <2.0 mV (95.0% vs. 74.2% vs. 57.1%, Log-Rank: p < .001). In the AF etiology of patients with AF recurrence, 9 of 14 patients who underwent the 2nd procedure had no PV reconnection, and 8 patients required the LA-PW isolation for their non-PV AF. CONCLUSION: UV criteria of LA-PW is a useful parameter for AF-recurrence post-PVI. Lower UV in LA-PW as an indication of electrical remodeling could indicate a higher risk of AF recurrence and the need for further therapeutic strategies.

Successful transvenous implantable cardioverter-defibrillator implantation supported by preceding 3D electro-anatomical mapping for a ventricular fibrillation survivor with surgically repaired congenitally corrected transposition of the great arteries: a case report.

Background: The atrial sites suitable for lead placement are limited after complex surgical atrial procedures, and lead placement can be challenging in patients with congenitally corrected transposition of the great arteries (ccTGA) after intracardiac repair. Case summary: A 34-year-old man with ccTGA, who had undergone a double-switch operation with combined Senning and Jatene operations at the age of 14 was transferred to us. He experienced faintness and suffered cardiopulmonary arrest, and electrocardiography revealed ventricular fibrillation. After conversion to sinus rhythm by urgent external defibrillation, sinus bradycardia was revealed. Electrophysiological study was done using a three-dimensional (3D) mapping system (Ensite®) to evaluate the electrical condition of atria and to decide whether atrial lead can be transvenously placed. The electrical potential of the functional right atrium was good in the lateral or posterior wall, but the threshold was high. By contrast, the roof of the functional right atrium beyond cavoatrial junction was characterized by low voltage, but in a limited region of the roof of right atrium, the threshold was satisfactory and the electrical potential was normal. Thus, 3 weeks later, we implanted a transvenous implantable cardioverter-defibrillator (ICD). We used a 3D mapping system to place the atrial lead in the limited region of the roof of the right atrium mentioned above, the threshold was 0.7 V. Discussion: Electrophysiological examination using a 3D mapping system before implantation of a dual-chamber ICD is useful because atrial sites suitable for lead placement are limited in patients.

Recurrent Early Coronary Stent Thrombosis under Chronic Disseminated Intravascular Coagulation.

A 62-year-old Japanese man presented with chest pain indicating that acute myocardial infarction had occurred. Eleven years earlier, he underwent a splenectomy due to idiopathic portal hypertension. Coronary angiography revealed diffuse stenosis, with calcification in the left anterior descending coronary artery (LAD). We performed a primary percutaneous coronary intervention (PCI). We deployed two drug-eluting stents with sufficient minimal cross-sectional stent area by intravascular ultrasound and thrombolysis in myocardial infarction (TIMI) 3 flow. The initial laboratory examination revealed chronic disseminated intravascular coagulation (DIC). On the 8th hospital day, he developed chest pain indicating early coronary stent thrombosis, although he had been prescribed dual antiplatelet therapy. We performed an emergent second PCI, and the TIMI flow grade improved from 0 to 3. Clopidogrel was replaced with prasugrel. On the 18th hospital day, we detected a repeated coronary stent thrombosis again. We performed a third PCI and the TIMI flow grade improved from 0 to 3. After anticoagulation therapy with warfarin, the DIC was improved and his condition ran a benign course without the recurrence of stent thrombosis for 1 month. Contrast-enhanced CT showed portal vein thrombosis. This patient's case reveals the possibility that the condition of chronic DIC can lead to recurrent stent thrombosis. Stent thrombosis is infrequent, but remains a serious complication in terms of morbidity and mortality. Although stent thrombosis is multifactorial, the present case suggests that DIC is a factor in stent thrombosis. To prevent stent thrombosis after PCI under DIC, anticoagulation might be a treatment option in addition to antiplatelet therapy.