The INVICTUS rheumatic heart disease research program: Rationale, design and baseline characteristics of a randomized trial of rivaroxaban compared to vitamin K antagonists in rheumatic valvular disease and atrial fibrillation.

BACKGROUND: Rheumatic heart disease (RHD) is a neglected disease affecting 33 million people, mainly in low and middle income countries. Yet very few large trials or registries have been conducted in this population. The INVICTUS program of research in RHD consists of a randomized-controlled trial (RCT) of 4500 patients comparing rivaroxaban with vitamin K antagonists (VKA) in patients with RHD and atrial fibrillation (AF), a registry of 17,000 patients to document the contemporary clinical course of patients with RHD, including a focused sub-study on pregnant women with RHD within the registry. This paper describes the rationale, design, organization and baseline characteristics of the RCT and a summary of the design of the registry and its sub-study. Patients with RHD and AF are considered to be at high risk of embolic strokes, and oral anticoagulation with VKAs is recommended for stroke prevention. But the quality of anticoagulation with VKA is poor in developing countries. A drug which does not require monitoring, and which is safe and effective for preventing stroke in patients with valvular AF, would fulfill a major unmet need. METHODS: The INVestIgation of rheumatiC AF Treatment Using VKAs, rivaroxaban or aspirin Studies (INVICTUS-VKA) trial is an international, multicentre, randomized, open-label, parallel group trial, testing whether rivaroxaban 20 mg given once daily is non-inferior (or superior) to VKA in patients with RHD, AF, and an elevated risk of stroke (mitral stenosis with valve area ≤2 cm2, left atrial spontaneous echo-contrast or thrombus, or a CHA2DS2VASc score ≥2). The primary efficacy outcome is a composite of stroke or systemic embolism and the primary safety outcome is the occurrence of major bleeding. The trial has enrolled 4565 patients from 138 sites in 23 countries from Africa, Asia and South America. The Registry plans to enroll an additional 17,000 patients with RHD and document their treatments, and their clinical course for at least 2 years. The pregnancy sub-study will document the clinical course of pregnant women with RHD. CONCLUSION: INVICTUS is the largest program of clinical research focused on a neglected cardiovascular disease and will provide new information on the clinical course of patients with RHD, and approaches to anticoagulation in those with concomitant AF.

[Impact of CHA2DS2 VASc score on substrate for persistent atrial fibrillation and outcome post catheter ablation of atrial fibrillation].

OBJECTIVE: To explore if CHA2DS2 VASc score can predict substrate for persistent atrial fibrillation ( AF) and outcome post catheter ablation of AF. METHODS: From January 2011 to December 2012,116 patients underwent catheter ablation of persistent AF in our department and were enrolled in this study. CHA2DS2VASc score was calculated as follows: two points were assigned for a history of stroke or transient ischemic attack and age ≥ 75 and 1 point each was assigned for age ≥ 65, a history of hypertension, diabetes,recent cardiac failure, vessel disease, female. Left atrial geometry ( LA) was reconstructed with a 3.5 mm tip ablation catheter with fill-in threshold 10 in CARTO system. The mapping catheter was stabled at each endocardial location for at least 3 seconds for recording. The electrogram recordings at each endocardial location were analyzed with a custom software embedded in the CARTO mapping system. Interval confidence level (ICL) was used to characterize complex fractionated atrial electrograms (CFAEs) . As the default setting of the software, ICL more than or equal to 7 was considered sites with a highly repetitive CFAEs complex. CFAEs index was defined as the fraction of area of ICL more than or equal to 7 to the left atrial surface. The CFAEs index and outcome of catheter ablation among different CHA2DS2VASc groups were compared. RESULTS: Of the 116 patients, CHA2DS2VASc was 0 in 33 patients, 1 in 31 patients and ≥ 2 in 52 patients. Left atrial surface ((121.2 ± 18.9) cm2, (133.6 ± 23.8) cm2, (133.9 ± 16.1) cm2, P = 0.008), left atrial volume ((103.6 ± 24.8) ml, (118.3 ± 27.8) ml, (120.9 ± 20.9) ml, P = 0.005) and CFAEs index (44.6% ± 22.4%, 54.2% ± 22.2%, 58.7% ± 23.1%, P = 0.023) increased in proportion with increasing CHA2DS2VASc. ICLmax, ICLmin and CFAEs spatial distribution were similar among the three groups. During the mean follow-up of (13 ± 8) months, the recurrence rate were 36.4%, 35.5%, 55.8% among the three groups (P = 0.025). CONCLUSION: A high CHA2DS2VASc score is associated with extensive AF substrate and higher recurrence rate post catheter ablation of persistent AF.