A single-center experience with the Sorin Mitroflow pericardial aortic valve: hemodynamics up to five years.

BACKGROUND AND AIM OF THE STUDY: The authors' institution participated in a 28-center FDA Investigational Device Exemption study to evaluate the Sorin Mitroflow pericardial aortic bioprosthesis. Six high-enrolling sites evaluated patients on an annual basis as part of an ongoing hemodynamic study. These data represent patients followed for an average of five years after implant, with annual echocardiography. METHODS: Seventy-one patients were entered into the study and constitute the basis of this review. Mean follow up was 3.3 +/- 2.0 years (range: 0-5.5 years), with a cumulative follow up of 233 patient-years. The mean patient age was 73.8 years (range: 45-89 years), and 52% were males. The majority of aortic valve lesions were stenosis (63%) or mixed (30%), and nine patients (12.7%) were reoperations. Sixty-one patients (86%) had concomitant procedures, the most common being coronary artery bypass grafting (70%). RESULTS: A total of 281 echocardiograms was obtained from the patients over a five-year period. The largest number of echocardiograms was obtained with 23-mm valve implants (n = 122), followed by 25 mm valve implants (n = 87). The early baseline (30-day) mean gradient was < or = 10 mm in all patients. The mean gradient decreased as the valve size increased (21 mm valve gradient = 10.0 +/- 5.6 mmHg; 27 mm valve gradient = 6.2 +/- 2.2 mmHg). The mean increase in gradient at five years was < 7 mmHg, with a trend towards increased gradients at smaller valve sizes. The effective orifice area (EOA) showed a trend to decline slightly with 21 mm valves (from 1.5 to 1.2 cm2) and 23 mm valves (1.4 to 1.2 cm2), but there was either no change or a slight increase in larger-size valves. Left ventricular mass regression occurred mainly within the first year (18.9%), but then remained stable throughout the study period. No greater than mild prosthetic aortic valve regurgitation was observed over the study period. CONCLUSION: The Sorin Mitroflow aortic valve provides excellent hemodynamic results up to five years, with minimal increase in mean gradients, acceptable peak gradients, and good EOAs with all valves sizes.

Techniques of surgical tracheostomy.

Tracheostomy has become one of the most commonly performed procedures in the critically ill patient. Variations in technique and expertise have led to a wide range of reported procedural related morbidity and rarely mortality. The lack of prospective, controlled trials, physician bias and patient comorbidities further confound the decisions regarding the timing of tracheostomy. With careful attention to anatomy and technique, the operative complication rate should be less than 1%. In such a setting, the risk-benefit ratio of prolonged translaryngeal intubation versus tracheostomy begins to weight heavily in favor of surgical tracheostomy. At exactly what point this occurs remains undefined, but certainly by the tenth day of intubation, if extubation is not imminent, arrangements should be made for surgical tracheostomy by a team experienced with the chosen technique.

Ventilatory dependency after cardiovascular surgery.

OBJECTIVES: Ventilatory dependency is a widely recognized complication of cardiovascular surgery, often leading to tracheostomy. Some risk factors for its occurrence have been documented. Less well characterized are short- and long-term outcomes. Therefore, objectives were to identify risk factors for ventilatory dependency, assess its short- and long-term outcomes, and determine impact of tracheostomy. METHODS: From January 1998 to September 2001, 12,777 patients underwent cardiovascular surgery and survived at least 72 hours. Of these patients, 704 (5.5%) developed ventilatory dependency (cumulative intubation >72 hours); 185 (26%) underwent tracheostomy. Preoperative, intraoperative, and intensive care unit admission data were used sequentially to understand predictors of ventilatory dependency. Outcomes were analyzed by time-related methods, and impact of tracheostomy was assessed using competing-risks analysis. RESULTS: Hemodynamic status on intensive care unit admission (low cardiac output, vasopressor use, pulmonary hypertension; P < .0001) and early postoperative events (stroke, bacteremia; P < .0001) were more important than preoperative and intraoperative variables in predicting ventilatory dependency. Survival at 30 days, 1 year, and 5 years thereafter was 76%, 49%, and 33% and was strongly associated with favorable hemodynamic status. By 28 days, 24% of patients received tracheostomy; survival at 30 days and 2 years thereafter was 74% and 26%, considerably below anticipated survivals of 84% and 58%. CONCLUSIONS: Improved operative and postoperative strategies to preserve myocardial function and restore hemodynamics should decrease the prevalence of ventilatory dependency. Unfortunately, preoperative models of ventilatory dependency are too insensitive for clinical use. Tracheostomy and its outcome are also poorly predicted, highlighting the complex interaction of events altering patients' conditions before and after tracheostomy.

Tracheostomy after cardiovascular surgery: an assessment of long-term outcome.

OBJECTIVE: To ascertain long-term survival, identify risk factors for death, and document complications of tracheostomy after cardiovascular surgery. METHODS: Between January 1, 1998, and September 1, 2001, 188 (1.4%) of 13,191 patients undergoing cardiovascular surgery had tracheostomy for respiratory failure 5 to 79 days (median, 14 days) after surgery. Factors associated with mortality were identified in the hazard function domain, and mode of death and complications of tracheostomy were determined by follow-up. RESULTS: Survival was 75%, 50%, and 31% at 30 days, 3 months, and 2 years, respectively. The most important risk factors for death were older age (P = .004) and variables representing deteriorating hemodynamic (P < .0001), respiratory (P < .0001), and renal (P = .0001) function between the index cardiovascular operation and tracheostomy. The mode of death was isolated respiratory failure in only 21 (16%) of 130 patients, but multisystem organ failure in 71 (55%). Follow-up of 58 survivors identified voice complaints in 13 (24%), tracheal stenosis in 5 (9.2%), and permanent tracheostomy in 3 (6%). CONCLUSIONS: Only one third of patients undergoing tracheostomy after cardiovascular surgery survive, because it is used primarily in those with deteriorating function of multiple organ systems. Although tracheostomy may enhance patient comfort and simplify nursing care, selection algorithms need to be developed if survival is the goal of the intervention.

Is reoperation still a risk factor in coronary artery bypass surgery?

BACKGROUND: Hospital mortality for reoperative coronary artery bypass grafting (CABG) is approaching that of primary CABG. This raises two questions: (1) has experience neutralized the risk of reoperation attributable to its greater difficulty, or (2) has experience neutralized the risk attributable to the higher-risk profile of reoperative patients?. METHODS: From 1990 to 2003, 21,568 CABG procedures were performed, of which 4,518 (21%) were reoperations: 3,919 first, 552 second, 43 third, 3 fourth, and 1 fifth. Reoperative patients had a higher-risk profile than primary patients, with more vascular disease, left ventricular dysfunction, and coronary artery disease (all p < 0.0001). Logistic regression was used to identify factors associated with hospital death and to develop a propensity score for reoperation, which was used to (1) adjust multivariable analyses of death and (2) compare outcomes in matched patients. RESULTS: Hospital mortality was 4.3% (168 of 3,919) for first reoperation, 5.1% (28 of 552) for second, and 6.4% (3 of 47) for third or more, compared with 1.5% (263 of 17,050) for primary operations. Risk of both primary and reoperative CABG decreased with experience (p > 0.0002); however, reoperative risk fell markedly in the mid-1990s. In both the overall and matched-pairs analyses, reoperation was a risk factor before 1997 (p < or = 0.008), but not after (p = 0.2). Reoperation within 1 year of previous CABG increased risk (p < 0.0001). Risk attributable to left ventricular dysfunction decreased with experience (p = 0.05). CONCLUSIONS: Hospital mortality for reoperative CABG has been consistently higher than for primary operation, but this difference has narrowed considerably. Patient characteristics, not reoperation itself, now have greater influence.

Survival after simultaneous left ventricular free wall, papillary muscle, and ventricular septal rupture.

Cardiac rupture is a catastrophic complication of acute myocardial infarction. The three potential sites of rupture are the left ventricular free wall, interventricular septum, and papillary muscle. Without rapid surgical correction, each of these complications typically leads to cardiogenic shock, multiorgan failure, and death. Postmortem analysis has identified a small number of cases in which myocardial infarction led to rupture at more than one of these sites; however, there are no reports of survival from such an event. We report a case involving rupture at all three sites in the same patient, emphasizing the importance of transesophageal echocardiography and surgical management.