title: Chitra heart valve: results of a multicenter clinical study.
abstract: OBJECTIVE
  The Chitra tilting disc valve was developed in India to meet the need for a low-cost cardiac valve. The valve has an integrally machined cobalt-based alloy cage, an ultra-high molecular-weight polyethylene disc, and a polyester suture ring. An important feature of this valve is its soft closing sound, by virtue of a plastic occluder.
  
  
  METHODS
  Between December 1990 and January 1995, 306 patients underwent isolated aortic (AVR, n = 101) or mitral valve replacement (MVR, n = 205) at six institutions in India. The early mortality rate was 6.9% (seven after AVR; 14 after MVR). A total of 285 survivors was followed up until September 1998; total follow up was 1212 patient-years (pt-yr) (AVR, 445 pt-yr; MVR, 767 pt-yr).
  
  
  RESULTS
  There were 52 late deaths (4.3%/pt-yr; AVR 2.2%/pt-yr; MVR 5.5%/pt-yr). Thirty-five deaths were valve-related (23 were due to unknown causes). One AVR patient (0.2%/pt-yr) and 12 MVR patients (1.6%/pt-yr) developed valve thrombosis, and embolic episodes occurred in 25 patients (seven after AVR, 1.6%/pt-yr; 18 after MVR, 2.4%/pt-yr). Bleeding events and infectious endocarditis occurred infrequently (AVR 0.9 and 0.7%/pt-yr; MVR 0.4 and 0.5%/pt-yr, respectively). There was no incidence of paravalvular leak or structural dysfunction of the valve. Actuarial survival rates at seven years were 82.4+/-4.0% for AVR and 65.2+/-5.0% for MVR. During the same interval, thrombus-free and embolism-free survival after AVR and MVR occurred in 98.9+/-1.1% and 94.1+/-1.9%, and 92.3+/-2.8% and 82.1+/-5.7% of patients, respectively. Freedom from all valve-related mortality and morbidity at seven years was 81.5+/-4.1% after AVR, and 64.2+/-5.1% after MVR.
  
  
  CONCLUSIONS
  The Chitra valve appears to be safe and to have performance comparable with that of other currently used tilting disc valves. This valve costs substantially less than other valves, and is therefore within reach of a larger subset of Indian patients.
authors.affiliation: Dept. of CVTS, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, India.
authors.forename: R
authors.initials: R
authors.lastname: Sankarkumar
authors.forename: G S
authors.initials: GS
authors.lastname: Bhuvaneshwar
authors.forename: R
authors.initials: R
authors.lastname: Magotra
authors.forename: S
authors.initials: S
authors.lastname: Muralidharan
authors.forename: R S
authors.initials: RS
authors.lastname: Rajan
authors.forename: D
authors.initials: D
authors.lastname: Saha
authors.forename: K S
authors.initials: KS
authors.lastname: Subba Rao
authors.forename: M S
authors.initials: MS
authors.lastname: Valiathan
authors.forename: S
authors.initials: S
authors.lastname: Radhakrishna
authors.forename: A V
authors.initials: AV
authors.lastname: Ramani
mesh_terms: D000293:Adolescent; D000328:Adult; D000925:Anticoagulants / Q000627:therapeutic use; D001021:Aortic Valve / Q000601:surgery; D002648:Child; D002669:Child Welfare; D003722:Dental Alloys / Q000627:therapeutic use*; D004617:Embolism / Q000209:etiology / Q000401:mortality / Q000628:therapy; D004697:Endocarditis, Bacterial / Q000209:etiology / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000150:complications / Q000628:therapy; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D006470:Hemorrhage / Q000209:etiology / Q000401:mortality; D006801:Humans; D015994:Incidence; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D011474:Prosthesis Design; D016459:Prosthesis-Related Infections / Q000209:etiology / Q000401:mortality; D012086:Reoperation; D012214:Rheumatic Heart Disease / Q000150:complications / Q000628:therapy; D012307:Risk Factors; D015996:Survival Rate; D015912:Thrombolytic Therapy; D013927:Thrombosis / Q000209:etiology / Q000401:mortality / Q000628:therapy; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; C409647:Chitra; D003722:Dental Alloys