Gastón Chamorro S

Endocarditis infecciosa: análisis de 261 casos y resultados del tratamiento con un enfoque multidisciplinario

Background: Early diagnosis, an effective treatment and prompt recognition of complications are essential to improve the prognosis of infective endocarditis (IE) Aim: To report the results of a multidisciplinary approach to diagnosis and management of patients with IE at the Universidad Catolica de Chile Hospital. Patients and methods: The clinical history, diagnosis, treatment and outcome of 261 episodes (Duke criteria) of IE admitted between January 1980 and January 1999 were analyzed. These included 185 episodes of native, 73 of prosthetic valve and 3 of nonvalvular IE. Results: Sixty nine percent of patients were men and the mean age was 49 ± 16 years. Seventy five percent had a definite diagnosis of IE (Duke). S. viridans, staphylococci and enterococci together constituted 85% of the isolated bacterial strains. Twenty seven had culture-negative IE, related to a high incidence of antibiotic therapy prior to diagnosis. Transesophageal echocardiography was performed in 102 cases and it detected vegetations in 91% of aortic and 96% of mitral IE, rupture or prosthesis dehiscence in 67% of aortic and 52% of mitral IE and abscesses in 51% of aortic and 15% of mitral IE. Fifty one percent developed heart failure and 34% had embolic events. S. aureus IE was associated to a higher incidence of embolic events, complications which contraindicated surgery and increased mortality rate (27%). Of all patients, 40% were treated exclusively with antibiotics, 52% were operated on and 8% had surgical indication but were nonoperable because of serious complications. The overall mortality was 16.3%: 13% in the medical, 9% in the surgical and 81% in the non-operable groups. The type of treatment and mortality rates did not differ between IE of native valves and prosthetic valves. Long term follow up showed survival rates of 73% at 5 years and 66% at 10 years. Conclusion: A multidisciplinary approach may be very helpful to improve the prognosis of IE. (Rev Med Chile 2000; 128: 708-20).

Insuficiente control de factores de riesgo en prevención secundaria cardiovascular

One year survival was 96%(all 13 deaths were of cardiac origin). Eighty seven percent of patients were free of majorcardiovascular events. At discharge from hospital and at the end of follow up 49% and 44% hada total cholesterol over 200 mg/dl respectively, 9,6% and 20,8% had systolic pressure over 140mmHg. There was no diastolic hypertension in these patients, 27% and 31% had a body massindex over 25 kg/m

Resultados alejados de la cirugía reconstructora de la insuficiencia mitral

Background: Surgical repair is the procedure of choice for mitral insufficiency since it preserves better left ventricular structure and function. Aim: To assess the long term clinical and echocardiographic results of mitral valve reconstructive surgery. Material and methods: A review of clinical and echocardiographic data of 68 patients (34 male, age range 17 to 82 years), subjected to surgical mitral valve repair between December 1991 and March 1998. Preoperative functional capacity of these patients was 2.96 ± 0.7. Surgical repair was assessed using transesophagic echocardiography in all subjects. Results: The etiology of mitral insufficiency was degenerative in 43 patients, rheumatic in 10, infectious in 6, ischemic in 5 and miscellaneous in 4. The most frequent pathological findings were dilatation of the mitral ring in 42% of patients, chordae tendinae rupture in 32% and enlargement in 24%. A mitral anuloplasty was done in 90% of patients, a cuadrilateral resection of posterior leaflet in 52% and chordae tendinae transference in 12%. An additional surgical procedure was done in 34% of subjects. Three patients died during hospitalization (4.4%). During the follow up of 36.5 ± 22.3 months, five patients died and one required a mitral valve replacement. The actuarial survival probability was 95.3 ± 2.6% at one year and 83.5 ± 6.5% at five years. The reoperation free survival was 100% at one year and 97.4 ± 2.5% at five years. At the end of follow up the functional capacity improved to 1.25 ± 0.4. Echocardiography showed absence of mitral insufficiency in 48.4% of patients, minimal, mild and moderate insufficiency in 35.5, 14.5 and 1.6% of patients respectively. Conclusions: Surgical valve reconstruction in mitral insufficiency has satisfactory long term results and should be the procedure of choice for eligible patients.

Cirugía valvular reparadora en endocarditis infecciosa

Background: Valve replacement has been the treatment of choice for patients with valvular complications of infectious endocarditis (IE). However, excellent results with valve repair allowed it to become a new therapeutic alternative for these patients. Aim: To evaluate the results of valve repair in patients with valvular complications of IE. Patients and Methods: From January 1991 to December 2000, 14 patients with valvular complications of IE underwent valve repair. Mean age was 37.9 ± 14.9. Results: New York Heart Association (NYHA) class was 2.8 ± 0.9. IE was located in the aortic in 6 (42%), in the mitral valve in 4 (29%) and in both valves in 4 cases (29%). Surgical indication was hemodynamic in 50% of the cases, echocardiographic in 29% and septic in 21%. Five aortic valves were bicuspid, 3 mitral valves were myxomatous and the rest were normal. The most common septic lesions were vegetations and leaflet perforations. A total of 23 aortic and 21 mitral valve repair procedures were performed. There were no deaths. Only 1 patient had a surgical complication (renal failure and prolonged mechanical ventilation). Follow-up was 100% complete. There was not late mortality. One patient with bone marrow aplasia required reoperation for a new episode of IE 19 months later. At the end of the follow-up NYHA class was 1.3 ± 0.6 and echocardiography showed a mild or absence of valve regurgitation in most patients. Conclusions: Valve repair surgery in IE has good results, with advantages over valve replacement (Rev Med Chile 2004; 132: 307-15). (Key Words: Cardiovascular surgical procedures; Endocarditis, bacterial; Surgical procedures, operative)

Resultados alejados de la cirugía reparadora de la insuficiencia mitral degenerativa

Background: Mitral valve repair is probably the procedure of choice for the surgical treatment of degenerative mitral insufficiency. Aim: To evaluate the late results of mitral valve repair in degenerative mitral insufficiency. Patients and method: The records of 88 patients who underwent mitral valve repair for degenerative mitral insufficiency from December 1991 through June 2002 were reviewed. Mean age was 59.9 years (range 22 to 82). At least moderate mitral insufficiency was present in every patient. Mean left atrial diameter was 55 mm and mean end diastolic and end systolic left ventricular diameters were 61 and 37 mm respectively. Results: The most common underlying lesion was ruptured chordae tendineae (66%) and posterior leaflet prolapse (68%). The surgical procedure most frecuently performed was quadrilateral resection of the posterior leaflet (68%). A Carpentier-Edwards ring was placed in 97% of patients. An associated procedure was performed in 34%. Operative mortality was 2.3%. A complete follow up was obtained in 93% of cases with a mean of 54±36 months. Overall survival rate was 98% at one year, 88% at 5 and 82% at 10 years. Free of cardiac death rates were 94% at 5 and 89% at 10 years. Only 2 patients were reoperated during follow up, resulting in a 98% reoperation free rate follow up. Functional class improved in all patients at the end of follow up. Late echocardiographic evaluation showed absent or minimal mitral regurgitation in 83% and mild mitral regurgitation in 17%. Conclusion: Good late results have been obtained with mitral valve repair, avoiding the inconveniencies of prosthetic replacement. Therefore, mitral valve repair should be the procedure of choice to treat degenerative mitral insufficiency (Rev Med Chile 2003; 131: 1355-64). (Key Words: Mitral valve insufficiency)

Tratamiento de la insuficiencia cardíaca avanzada mediante trasplante de corazón

Background: Heart transplantation currently provides the most effective treatment for advanced heart failure. However, medical therapy for this condition has also improved, heart donors are scarce and the cost of the procedure is high. Therefore the indications and management of these patients need reevaluation. Aim: To analyze the results of 24 patients submitted to heart transplantation for end-stage heart failure needing repeated hospitalizations and i.v. inotropes for compensation. Patients and methods: The group was comprised by 21 men and 3 women with a mean age of 36.8 years, mean left ventricular ejection fraction 19±4.5%, mean systolic pulmonary artery pressure 48±13 mmHg (24-70) and mean pulmonary vascular resistance 2.6 Wood Units (1-5). Fourteen patients (58%) had a previous median sternotomy. Immunosupression did not include induction therapy and steroids were discontinued early. Results: Operative mortality was 4% at 30 days. Actuarial survival at one year was 90% and at 5 years 72%. Freedom from rejection at one year was 76% and at 5 years 50%. Freedom from infection was 70% at one year and 56.5% at five years. All patients with more than 3 months of follow-up were in functional class I. Conclusions: These results justify the proposed modifications for transplantation protocols (Rev Med Chile 2001; 129: 9-17).

Experiencia de 36 años con marcapasos implantables: Un análisis histórico

Background: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. Aim: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. Material and methods: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificacion de Chile (Chilean Civil and Identification Registry). Results: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74% from 1988 to 1998. Complication rate was 42% in the 1963-1976 study period, it decreased to 10.6% in the 1977-1987 study period, and to 5.6% by 1988-1998. Only two patients died during surgery in the study period (0.08%). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52% at ten years, 33% at 15 years, and 21% at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. Conclusions: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures (Rev Med Chile 2002; 130: 132-42)

Cirugía de la insuficiencia mitral isquémica

Background. Ischemic mitral regurgitation (IMR) is a severe condition which may be best treated by surgery, nowithstanding a relatively high mortality rate. Objectives. To evaluate the results of mitral valve replacement or repair in patients with IMR. Patients and methods. Retrospective review of the clinical records in 29 patients with IMR who were surgically treated from 1990 to 1999. They represent 8% of surgical procedures on the mitral valve. Results. Mean age was 67 ± 9 years. Surgery was performed urgently in 19 patients (66,5%). NYHA functional class was 3.4 ± 0.8. The mechanism of IMR was annular dilatation and spreading of papillary muscles in 18 patients, papillary muscle rupture in 9 and fibrosis in 2. Mitral valve replacement was performed in 14 patients and mitral valve repair in 15. Twenty four patients (83%) had concomitant myocardial revascularization. Overall surgical mortality was 24%; 26% for mitral replacement and 13% for mitral valve repair (p=0.215). On follow up of 26±33 months, one year survival was 76±0.8% and 5 years survival was 59±12%. Excluding in hospital mortality, survival was 100% at one year and 78±14% at 5 years. Functional class improved in all survivors, to 1.4±0.5. Late echocardiographic evaluation of patients with mitral valve repair showed absence of mitral regurgitation in 58%, 1+ MR in 17% and 2+ MR in 25%. Conclusion. In spite of a high perioperative mortality, surgery for IMR is a valuable procedure for patients with an otherwise highly lethal disease (Rev Med Chile 2002; 130: 9-16)

Reemplazo parcial o total del arco aórtico: Experiencia en 23 pacientes

Between 1988 and 2002, 23 patients wereoperated. Seventeen had aortic dissection (10 acute and 7 chronic), five had an atheroscleroticaneurysm and one had a traumatic lesion. Thirteen patients were subjected to a replacement of thearch plus ascending aorta, six to a replacement of the arch plus descending aorta and four to areplacement of the arch, ascending and descending aorta. Seven patients had previous operation ofthe thoracic aorta. Arterial perfusion was done via the femoral artery, axillary artery or a combinationof both. A hypothermic circulatory arrest was induced in 22; it was associated with cerebral retroperfusion alone in 8 patients, antegrade cerebral perfusion in 5; isolated or associated axillaryperfusion was used in five patients. In seven, procedures on the aortic or mitral valve, or coronaryartery operations were added. Operative mortality was 26%, 3 of the 8 patients operated as anemergency and 3 of 15 elective operations. There was no mortality among those without dissection andof 7 chronic dissections, one died. All patients were followed for an average of 45 months. Two patientsrequired reinterventions on the aorta and one for colon cancer. There was one late death of unknowncause. Postoperative complications were agitation, bleeding and temporary vocal cord dysfunction.

Ciruguía reparadora de la válvula aórtica bicúspide insuficiente

Background: Surgical valve repair is a good alternative for correction of incompetent bicuspid aortic valve. Aim: To report the early and late surgical, clinical and ecochardiographic results of surgical repair of incompetent bicuspid aortic valves. Patients and methods: Retrospective review of medical records of 18 patients aged 19 to 61 years, with incompetent bicuspid aortic valve in whom a valve repair was performed. Four patients had infectious endocarditis and 17 were in functional class I or II. Follow up ranged from 3 to 113 months after surgery. Results: A triangular resection of the prolapsing larger cusp, which included the middle raphe, was performed in 17 cases; in 13 of these, a complementary subcommisural annuloplasty was performed. In the remaining case, with a perforation of the non-coronary cusp, a pericardial patch was implanted; this procedure was also performed in 2 other cases. In 3 cases large vegetations were removed. Postoperative transesophageal echocardiography showed no regurgitation in 11 patients (62%) and mild regurgitation in 7 (38%). There was no operative morbidity or mortality. There were no deaths during the follow-up period. In 3 patients (17%) the aortic valve was replaced with a mechanical prosthesis, 8 to 108 months after the first operation. Reoperation was not needed in 93%±6,4% at 1 year and 85%±9,5% at 5 years, these patients were all in functional class I at the end of the follow-up period. 60% had no aortic regurgitation, 20% had mild and 20% moderate aortic regurgitation on echocardiographic examination. A significant reduction of the diastolic diameter of the left ventricle was observed, but there were no significant changes in systolic diameter or shortening fraction. Conclusions: Surgical repair of incompetent bicuspid aortic valves has low operative morbidity and mortality and has a low risk of reoperation (Rev Med Chile 2005; 133: 279-86)