[The multicenter study on the registration and follow-up of low anticoagulation therapy for the heart valve operation in China]

OBJECTIVE

To investigate the optimal anticoagulation methods and monitoring strategy for Chinese patients undergoing heart valve replacement, which is potentially quite different from western populations.

METHODS

In this multicenter prospective cohort study, the anticoagulation and monitoring strategy data was acquired from 25 773 in-hospital patients in 35 medical centers and 20 519 patients in outpatient clinic in 11 medical centers from January 1st, 2011 to December 31th, 2015.

RESULTS

As for in-hospital patients, mean age of study population was (48.6±11.2) years old; main etiology of valve pathology was rheumatic (87.5%) origin among study cohort; 94.8% of study population received mechanical valve implantation; international normalized ratio (INR) monitoring (in all the study centers) and low-intensity anticoagulation strategy (31 hospitals chose target INR range of 1.5-2.5, and actual values of INR among 89.2% of 100 069 in-hospital monitoring samples were 1.5-2.5), with mean actual INR values of 1.84±0.53, and warfarin dosage of (2.82±0.93) mg/d were widely adopted among the study centers; strategies of in-hospital warfarin administration were similar in all the study centers; complication rates of low-intensity anticoagulation strategy were low in severe hemorrhage (0.02%), thrombosis (0.05%), and thromboembolism (0.05%) events, without anticoagulation-related death.As for 18 974 outpatient clinic patients, the follow-up rate was 92.47%, with a total of 30 012 patient-years (Pty). Anticoagulation-related morbidity and mortality rates were 0.67% and 0.15% Pty; major hemorrhage morbidity and mortality rates were 0.25% and 0.13% Pty; thromboembolism morbidity and mortality rates were 0.45% and 0.03% Pty.The mean dosage of warfarin daily dosage was (2.85±1.23) mg/d and INR value was 1.82±0.57.No significant regional difference in the intensity of anticoagulation therapy was noted during the study.

CONCLUSIONS

INR can be used as a normalized indicator for intensity of anticoagulation therapy in China.The optimal anticoagulation intensity with INR range from 1.5 to 2.5 is safe and effective for Chinese patients with heart valve replacement, and there is no significant regional difference in the intensity of anticoagulation therapy.

[Surgical treatment of left ventricular aneurysm]

From April 1972 to Dec. 1993, 152 cases underwent operation for left ventricular aneurysm (LVA) in Fuwai hospital. There were 143 males and 9 females with mean age of 49 years. Patients underwent ECG, chest X-ray (C/T 0.42-0.71), echocardiogram (LVEDP 0.267-6.27 kPa and cardiocoronary angiography (LVEF13-69%). There were 58 cases (38%) in NYHA class II, 82 cases (54%) in class III and 58 cases (7%) in class IV preoperatively. The total operative mortality was 9% with 7% of the last six-year. The main cause of the death was refrectory low cardiac output syndrome. Univariate analysis showed that the operative risk factors included ventricular arrhythmias, preoperative congestive heart failure (< 1 month), poor NYHA class, A-V condaction block. 138 discharged cases were followed up from 2-215 months (mean 36). There were 11 late deaths. The five-year and ten-year survival was 90% and 55% respectively. At the latest follow-up 44 cases (35%) were in NYHA class I, 62 (49%) in class II, 6 (6%) in class III and 2 (2%) in class IV. Our report demonstrated CABG is an effective treatment with good early and late results for LVA.

[Clinical and morphologic classification of valve replacement with giant heart]

From Apr. 1977 to Dec. 1992, 285 patients with giant heart (CTR > 0.70) underwent valve replacement. According to the index of cardiac chamber enlargement, the patients were clinically and morphologically classified in to four types. Type of left atrium (153 cases, 56.3%) is most common and has good surgical result. The operative mortality was reduced from 11.1% to 1.3%. Type of left ventricle (42, 15.2%) was high risk for surgical treatment, the operative mortality was 33.3%. Type of right cardiac enlargement (17 cases) is less common than other types, and is mainly for tricuspid valve incompetence. Type of total cardiac enlargement was found in 60 cases (22.1%), it was conventionally complicated with the disfunction of other organs with a higher operative mortality of 23.3%. We conclude that this classification represents the degree of cardiac chamber enlargement and the severity of heart disfunction, and has good coincidence with surgical result. It is helpful to identifying operative candidate for valve replacement with giant heart.

[Estimation of the effect of mitral valve correction]

From September 1958 to December 1992, 488 patients underwent mitral valve repair in Fuwai Hospital. Patients ages ranged from 49 days to 60.5 years (mean age 29.02 +/- 9.97 years). The cause of mitral valve disease was rheumatic in 415 patients (85.04%). 391 patients (80.12%) had isolated mitral valve disease and 97 patients (19.88%) had associated with aortic or tricuspid valve disease, or both. There were 167 patients (34.22%) with pure mitral stenosis, 106 patients (21.72%) with pure mitral regurgitation and 215 patients (44.06%) with both. 64.96% of the patients were in New York Heart Association (NYHA) III and IV before the operation. There were 433 patients (88.73%) with isolated mitral valve repair and 55 patients (11.27%) with mitral valve repair associated with other valve repair. The hospital mortality rate was 11.27% (7.00% after 1980). 7.39% of the patients were in NYHA III and IV after operation (P < 0.01). Follow-up was 92.38% complete and totaled 4824. 12 patient-years. The mean follow-up time was 12.3 +/- 8.83 years. The 5-year, 10-year and 20-year survival rates were 94.92%, 89.70% and 70.19%, respectively. The rate of reoperation was 4.16% (0.37%/pt-yr) and the one of thromboemboli was 5.54% (0.498%/pt-yr). The follow-up mortality and reoperation rate of rheumatic mitral valve disease were significantly higher than the other causes (P < 0.01). In hospital and follow-up results of the pure MI were better than the MS and MSI (P < 0.01). The better results were obtained in mitral annuloplasty with prosthetic valve ring.