Ricardo Zalaquett 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).

Mixoma cardiaco: Caracterización clínica, métodos diagnósticos y resultados alejados del tratamiento quirúrgico durante tres décadas de experiencia

Background: Cardiac myxoma is the most common primary cardiac tumor. Aim: To evaluate clinical aspects, diagnostic methods and surgical outcomes in patients with cardiac myxoma. Patients and Methods: All patients who underwent surgical resection of a cardiac myxoma between January 1973 and December 2004 at our institution, were identified and their medical records and diagnostic data reviewed. Results: Thirty seven patients identified (24 women), with a median age of 54 years (range 2-74). The most common symptom was dyspnea (51%), followed by embolism (24%) and cardiac murmurs (16%). The diagnosis was made by echocardiogram in 84% of patients. The mean tumor size was 4.9 ± 1.3 cm. The tumor was located in the left atrium in 83% of the patients, right atrium in 8% and left ventricle in 3%. Two patients had multiple tumors. Surgical approach was transeptal in 51%, left atriotomy in 22%, combined transeptal and roof of the left atrium in 19% and right atriotomy in 8%. The tumor and its attachment base were excised in one piece. There were two operative deaths and five late deaths. The mean follow-up was 11.5 years. The 5, 10, 15 and 20 years survival was 89%, 83%, 75% and 64%, respectively. Two patients had recurrence (5.4%), at 2 and 25 years after surgery, respectively, and the recurrence free survival at 10 and 25 years was 97% and 73%, respectively. Conclusions: Dyspnea was the most common symptom and echocardiogram the main diagnostic method. Surgical treatment was highly effective, with low mortality and recurrence rate, with good long term survival (Rev Med Chile 2008; 136: 287-95). (Key words: Echocardiography; Heart neoplasms; Myxoma)

Transección traumática aguda de la aorta torácica: Tratamiento endovascular

Traumatic rupture of the aorta has a near 80% mortality. Most patients die on the site of the accident. Conventional surgical repair of these lesions has a high morbidity and mortality, generally associated to the severity of associated lesions. Over the last decade, endovascular treatment has become an effective therapeutic alternative. We report a 40 years old male, that suffered a traumatic rupture of the descending thoracic aorta in a car accident. A successful endovascular repair was performed, installing an endoprothesis on the site of the lesion, using a femoral artery approach. The patient had a good postoperative evolution and was discharged from the hospital once complete rehabilitation of his associated lesions was obtained (Rev Med Chile 2003; 131: 309-13).

Operación de Fontan: resultados inmediatos y a mediano plazo con anastomosis cavopulmonar total

Background: During the last five years, 65 patients with univentricular heart have been treated surgically in our institution, according to a protocol of staged operations that have been previously reported. Aim: To evaluate the early and mid-term outcome of those patients that have completed their staging protocol by means of a Fontan procedure. Patients and Methods: Between April 1996 and June 2001, 23 patients (age 16 to 223 months) underwent a Fontan procedure, 15 with an intracardiac lateral tunnel technique and 8 with an extracardiac conduit. A retrospective review of their clinical, surgical, echocardiographic, angiographic and hemodynamic data was performed, trying to identify risk factors for both mortality and functional capacity (FC). Follow up was complete in all survivors. Results: Three patients died early after surgery (13.04%). Excessive pulmonary blood flow was a risk factor for early death (p= 0.03). One patient died at 14 months. Follow up was 29.9 months (1-63). For those who survived the operation, five years survival was 93.3%. The majority of patients are in FC I or II, with no related risk factors. Conclusions: Our current results are comparable with those of larger series. Patients reach good FC and mid-term survival, irrespective of type of single ventricle or the surgical strategy (Rev Med Chile 2002; 130: 1217-26).

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.

Factores determinantes en la aparición de fibrilación auricular post-cirugía de revascularización miocárdica: Un estudio prospectivo

Background: Atrial fibrillation (AF) is a relevant complication after coronary artery bypass grafting (CABG). However there is controversy regarding possible contributing factors. Aim: To study the incidence of AF, its risk factors and its repercussion on hospital stay and charges, in patients undergoing CABG. Material and methods: We prospectively collected information from all patients undergoing CABG in our institution, including demographic, surgical and laboratory variables. Exclusion criteria were chronic AF, recent onset AF and patients who needed additional surgical procedures. The primary endpoint was the incidence of AF during the hospital stay. Secondary endpoints were hospital length of stay and hospital charges. Results: We included 250 patients aged 62±9 years (199 males) in the analysis. Incidence of AF was 22% (54 patients). Multivariable analysis showed that age (Odds Ratio (OR) =1.10), previous CABG (OR =9.39), previous use of ACE inhibitors (OR =3.28) and aortic clamp >57 minutes (OR =3.97) were significantly associated with an increased risk of postoperative AF. Previous use of beta-blockers was associated with risk reduction (OR =0.43). Patients who developed AF had a longer hospital stay (p <0.001) and higher hospital charges (p =0.003). Conclusion: AF is a frequent complication in patients undergoing CABG. Risk factors are age, time of aortic clamp, previous CABG and ACE inhibitors. Beta-blockers may prevent its occurrence. Furthermore, AF has a negative impact on both hospital stay and hospital charges (Rev Med Chile 2007; 135: 967-74).

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)

Tratamiento endovascular del trauma de aorta descendente

Mortality of traumatic aortic lesions is over 80%. Agroup of those who survive, develop a chronic pseudo aneurism, usually asymptomatic, that isdetected during imaging studies. Since conventional surgical treatment of traumatic aorticlesions has a great mortality, endovascular treatment has been used as an alternative treatmentin the last decade.

Cirugía paliativa mediante operación de Norwood en distintas formas de corazón univentricular: resultados quirúrgicos inmediatos

: Norwood procedure is used as the first stage in thepalliative treatment of the hypoplastic heart syndrome and can be used, with some technicalmodifications, in other forms of univentricular heart with aortic stenosis or hypoplasia. Thesepatients have a high mortality (50%), derived from the procedure itself and from their abnor-mal physiological status.

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)