The role of soluble fibrin during anticoagulant therapy: a case report.

Warfarin, dabigatran, and apixaban are used for preventing ischemic stroke due to non-valvular atrial fibrillation (NVAF). However, it is often challenging to select the appropriate anticoagulant. We present the case of a 70-year-old male patient with persistent NVAF who developed pulmonary thromboembolism (PTE), deep vein thrombosis (DVT), and left atrial thrombus during anticoagulant therapy with warfarin. Intravenous recombinant tissue plasminogen activator was administered during his acute PTE. Heparin and apixaban were administered over 28 days; heparin was discontinued after the DVT resolved, while apixaban was administered to prevent ischemic stroke. Two days after heparin was discontinued, the patient experienced an ischemic stroke. Dabigatran was administered for secondary ischemic stroke prevention. Soluble fibrin (SF) levels remained elevated during treatment with heparin and apixaban and returned to normal after apixaban was replaced with dabigatran. Monitoring of SF may be useful as an index for selection of anticoagulants.

The relationship between paroxysmal atrial fibrillation and coronary artery spasm.

BACKGROUND: Coronary artery spasm has recently been reported as a complication of the ablation of atrial fibrillation (AF). It may be induced by cardiac autonomic nervous dysfunction during radiofrequency catheter ablation of AF. However, the underlying mechanism is not clear. We hypothesized that patients with paroxysmal AF coincidentally exhibit coronary artery spasm. METHODS: A total of 51 patients were enrolled in a case control study to clarify the relationship between paroxysmal AF and coronary artery spasm. We evaluated 17 patients with paroxysmal AF (AF group) and 34 patients without paroxysmal AF (control group). Drug-induced coronary artery spasm provocation tests were performed by intracoronary administration of acetylcholine or ergonovine. RESULTS: The AF group consisted of nine males and eight females, mean age 67 ± 10 years. The control group consisted of 16 males and 18 females, mean age 60 ± 14 years. In the AF group, coronary artery spasm was induced in 13 patients (76.5%) before AF ablation. In the control group, coronary artery spasm was induced in three patients (8.8%). Coronary artery spasm was more frequently induced in patients with AF (76.5% vs 8.8%; odds ratio, 33.583; 95% confidence interval, 6.5732-171.58; P < 0.0001). In the AF group, ventricular fibrillation and AF were recorded immediately after right coronary artery spasm induction in one patient. CONCLUSIONS: Paroxysmal AF patients have high positive rates of drug-provoked coronary artery spasm. Patients with paroxysmal AF may coincidentally exhibit coronary artery spasm.

Resolution of left atrial appendage thrombus with apixaban.

Left atrial appendage (LAA) thrombosis is an important cause of cardiogenic cerebral thromboembolism. Apixaban is a member of the class of novel oral anticoagulants (NOAC) and is superior to warfarin in preventing stroke or systemic embolism, causes less bleeding, and results in lower mortality in patients with atrial fibrillation. There are few reports of resolution of LAA thrombus with other NOAC. We present a 72-year-old male patient with persistent atrial fibrillation associated with left atrial thrombus. Sixteen days of apixaban treatment showed complete thrombus resolution. In this study, soluble fibrin and D-dimer levels decreased without prolongation of international normalized ratio (INR) and activated partial thromboplastin time (APTT).

The relationship between right ventricular lead position and paced QRS duration.

BACKGROUND: The relationship between the anatomical location of right ventricular pacing site and paced QRS duration is unclear. In this study, we aimed to investigate the relationship between right ventricular pacing site and paced QRS duration using cardiac angiography. METHODS: Fifty patients were implanted with pacemakers. The right ventricular lead position was determined from the findings of cardiac angiography and the paced QRS duration was measured. Cardiac angiography was used to display the right ventriculogram (RVG) and the left ventriculogram (LVG). The RVG view was divided into three areas and the LVG view was divided into four areas. RESULTS: The paced QRS duration value was significantly longer in the right ventricular apex area compared with the outflow and inflow areas (160 ± 15 ms vs 140 ± 15 ms, P = 0.02, and vs 133 ± 17 ms, P < 0.001, respectively), but those values were not statistically significantly different between the right ventricular outflow and the right ventricular inflow areas (140 ± 15 ms vs 133 ± 17 ms, P = 0.187). When assessed with LVG views, there were the statistically significant differences in the paced QRS duration values in all areas except the apex area. (LV mid-anterior: 147 ± 11 ms vs LV base: 127 ± 13 ms, P < 0.001, and vs LV mid-septum: 129 ± 12 ms, P = 0.001, respectively.) CONCLUSIONS: Cardiac angiography showed that there was a relationship between the anatomical right ventricular pacing site and paced QRS duration. Cardiac angiography can help determine the areas that produce shorter paced QRS duration.