Influence of body mass index in the postoperative evolution after lung transplantation.

OBJECTIVE: To study the influence of body mass index (BMI) on mortality and postoperative evolution in our 10-year experience as a lung transplant group. METHODS: The study included 256 lung transplants performed between June 1999 and June 2009. BMI was stratified into 4 groups (<20 kg/m2 underweight, 20-25 normal weight, 25-30 overweight, and >30 obese) for posttransplant mortality assessment (chi-square) in relation to age, gender, pathology, and transplant type (logistic regression). Time of mechanical ventilation and length of stay in the intensive care unit and in the hospital were also analyzed (Kruskal-Wallis test). RESULTS: BMI showed a normal distribution with a mean value of 24.8±5 kg/m2 (range, 13-38). Although postoperative mortality was greater in the overweight (23%) and obese (23.7%) groups, it did not reach statistical significance, nor was there a significant increase in the risk of death (odds ratios of 1.06 and 1.17, respectively). Risk of death was independent of BMI and was associated with pathology (lower in emphysema) and transplant type (lower in single lung). There were no significant differences in duration of mechanical ventilation (342 hours in obese patients vs 180 in normal weight; P=.7), length of stay in the intensive care unit (18 days in obese patients vs 14 in normal weight; P=.8), or length of hospital stay of patients that were discharged (37 days in obese patients vs 43 in normal weight; P=.8). CONCLUSIONS: In our experience, BMI is not a risk factor that significantly increases postoperative mortality, probably owing to an adequate selection of recipients and an optimal posttransplant management. However, it must be considered to be a relative contraindication, because it is established in the international guidelines, obliging a correct assessment of patients, especially if there are other comorbidities.

Complications during clinical evolution in lung transplantation: pulmonary embolism.

BACKGROUND: Medical complications after lung transplantation (LT) are frequent despite the advances in management. The objectives of this study were to evaluate the incidence and clinical features of pulmonary embolism (PE) among LT recipients in our center. PATIENTS AND METHODS: We performed a retrospective descriptive study of 280 patients who underwent LT between June 1999 and December 2009. RESULTS: Five patients with PE (1.78%) had undergone single LT due to idiopathic pulmonary fibrosis (IPF). PE developed in the transplanted lung and was bilateral in 2 cases. The only associated risk factor was obesity in 3 patients. The clinical presentation was nonspecific; the most frequent symptom being dyspnea. Computed tomography (CT) angiography and ventilation-perfusion scan were used for diagnosis. Patients underwent treatment with low-molecular weight heparin followed by oral anticoagulation. CONCLUSIONS: Our study showed a low incidence of PE (1.78%), although we focused exclusively on this condition, excluding other entities such as deep vein thrombosis. All PE events occurred in the subpopulation of IPF transplant recipients. Possibly some factors predisposed these patients to PE, although they remain unclear. Because PE can cause significant morbidity in LT recipients, it is important to include PE in the differential diagnosis among LT patients presenting with dyspnea, hypoxia, or clinical deterioration.

Lung transplantation as the first choice in emphysema.

INTRODUCTION: The indication for single or double lung transplantation in patients diagnosed with pulmonary emphysema is a topic of current debate. Our aim was to analyze the differences in the incidence of perioperative complications, survival, and quality of life between single and double lung transplantations. MATERIALS AND METHODS: From 1999 to 2008, 223 subjects underwent transplantation in our department, of whom 62 (28%) had a previous diagnosis of pulmonary emphysema. A retrospective study was performed to establish possible differences between group 1 (single lung) and group 2 (double lung) transplants analyzing overall survival using the Kaplan-Meier method and differences between groups using the log-rank test. Pearson chi-square test was used to compare the frequency of postoperative complications, bronchiolitis obliterans BOS acute rejection episodes, and infections. RESULTS: We included 62 patients who underwent transplantation for emphysema. Cumulative 5-year survival rate, excluding preoperative mortality, was 54% overall, 59% for group 1, and 56% for group 2. No significant differences were observed between the groups (P = .47). The frequency of BOS was 34% in group 1 and 42% in group 2 (P = .52). At least 1 acute rejection episode occurred in 52% of group 1 patients and 51% of group 2 patients (P = .98). Bacterial infections were experienced by 50% of group 1 patients and 54% of group 2 patients (P = .72). Fungal infections affected 10% of group 1 patients and 15% of group 2 patients (P = .71). Intraoperative complications were recorded in 27.6% of group 1 patients versus 54% of group 2 patients, a difference that was statistically significant (P = .032). CONCLUSIONS: The study results supported the decision of our group to consider single lung transplantation the treatment of choice in emphysema, which may be complemented with volume reduction surgery in the native lung or subsequent transplantation of the contralateral lung.

Results of "twinning procedure" in lung transplantation: experience in a single center.

INTRODUCTION: The major limiting factor for lung transplantation (LT), both worldwide and in Spain, is the number of suitable lung donors. This, together with the increased demand for LT, led us to propose the performance of 2 single lung transplantations simultaneously using the same donor (the "twinning procedure"). OBJECTIVE: The objective of this study was to analyze the outcome of patients who underwent transplantation with this procedure, assessing differences between the first and the second transplant. PATIENTS AND METHODS: From November 2001 to August 2008, 46 single lung transplantations (SLTs) were performed with 23 donors. RESULTS: The mean ischemia time was 258 minutes (median, 265) for the first transplantation and 312 minutes (median, 320) for the second transplantation. Primary graft dysfunction occurred in 5 patients (24%) in the first group and 9 in the second group (39%; P = .27). The median intubation time was 8 hours for the first and 6.5 hours for the second group. The mean hospital stay was 39 and 31 days, respectively. Postoperative mortality was 2 (8.7%) and 3 (13%) patient, respectively (P = .99). There was no significant difference in the incidence of acute rejection episodes, infections, or chronic rejections. Five-year survival rates were 67.9% for the first and 61.5% for the second (Kaplan-Meier). CONCLUSIONS: The performance of 2 SLTs using the same donor and in the same hospital was feasible with adequate planning, permitting better use of donors and reducing waiting list time and mortality. Our results showed no increased risk for recipients of the second transplant in the early postoperative and long-term periods.

Surgical risk factors associated with lung transplantation.

BACKGROUND: Despite years of experience with lung transplantation, perioperative morbidity rates remain high. The objective of this study was to analyze our series of lung transplant recipients, seeking to identify possible intra- and postoperative risk factors associated with mortality. PATIENTS AND METHODS: We performed a descriptive, retrospective study of 224 consecutive patients undergoing lung transplantation over a period of 112 months; we excluded retransplant procedures. We gathered details of the surgical procedure and postoperative period in the recovery unit. Univariate analysis using the chi-square test identified variables associated with the incidence of mortality. RESULTS: From 1999 to 2008, we performed 224 lung transplants, including 66% in men and 34% in women. Their overall mean age was 49.9 +/- 13.5 years. The conditions that led to transplantation were pulmonary fibrosis (38.4%); chronic obstructive pulmonary disease emphysema (29%); cystic fibrosis (10.7%); bronchiectasis (8.9%); pulmonary hypertension (3.1%); and other diseases (9.9%). A total of 124 (55.4%) patients underwent single and 100 (44.6%) received sequential bilateral lung transplantations. Surgical risk factors were identified in 51.3% of the cases, the most frequent being hemorrhage (25.3%), followed by severe pulmonary hypertension (14.7%) and cardiopulmonary bypass (12.1%). Greater perioperative mortality was detected among patients with surgical risk factors, namely, significantly related to cardiopulmonary bypass, pulmonary hypertension, and air leak. A higher frequency of surgical risk factors was observed among patients with bilateral lung transplantations and longer procedures, but they were not associated with greater perioperative mortality. Reoperation was necessary in 16 patients (7.2%), mainly owing to bleeding, it was not significantly related to mortality risk. CONCLUSIONS: The incidence of surgical risk factors in lung transplantation was high, especially in bilateral lung transplantations and prolonged procedures. Postoperative bleeding requiring reoperation was not frequent and not associated with increased preoperative mortality in our series.

Reoperation in the postoperative period of lung transplantation.

BACKGROUND: Lung transplantation (LTx) has been established as the last treatment option in certain lung diseases. It is not uncommon for complications to occur that require urgent reoperation. The objective of our study was to analyze the characteristics of lung transplant patients who required reoperation in the postoperative period. PATIENTS AND METHODS: We have conducted a retrospective descriptive study of 224 lung transplants from January 1999 to September 2008, excluding retransplants. A subgroup of 16 subjects (7.2%) required reoperations. RESULTS: These 16 individuals had a mean age of 49.38 +/- 14.32 years with 75% men and 25% women. The disease leading to LTx was emphysema in 6 (37.5%), pulmonary fibrosis in 5 (31.3%), pulmonary hypertension in 2 (12.5%) and bronchiectasis, cystic fibrosis, and lymphangioleiomyomatosis in 1 each (6.3%). Preoperatively, 40% were taking corticosteroids. Double lung transplantation was performed in 56.3% and single lung in 43.7%. LTx surgery was prolonged in 68.8% of patients and intraoperative complications were more frequent than in the other patients (P = .041). The causes for reoperation were bleeding in 13 (of these, 5 had severe adhesions and 4 required extracorporeal circulation during LTx); bronchial dehiscence in 1; wall dehiscence in 1; and vascular stenosis in 1. At the end of the study, 62.5% were alive and among the 6 who died, 3 succumbed as a result of the surgery. Most subjects underwent late reoperation after a mean of 16 days from transplantation (range, 1-55). The need for reoperation was not associated with greater perioperative mortality. CONCLUSIONS: The incidence of reoperation in the postoperative period was low in our series. The main cause was bleeding. In more than half of the cases, LTx surgery was prolonged and intraoperative complications were more frequent. The need for reoperation was not associated with greater perioperative mortality.

Prognostic power of dobutamine echocardiography after uncomplicated acute myocardial infarction in the elderly.

STUDY OBJECTIVES: To assess the prognostic value of dobutamine-atropine stress echocardiography (DSE) after uncomplicated acute myocardial infarction (AMI) in elderly patients. DESIGN: We analyzed 59 consecutive patients (42 men) aged > or = 70 years (mean +/- SD age, 75 +/- 4 years) who underwent DSE within 10 days after uncomplicated AMI. DSE was carried out following the standard protocol. Five myocardial responses were considered: (1) negative, (2) sustained improvement of contractility, (3) biphasic response (initial improvement followed by worsening), (4) worsening of contractility in the infarcted area, and (5) worsening at a distance. RESULTS: Mean follow-up duration was 13 +/- 8 months. Twenty-one patients had an event: cardiac death (n = 5), myocardial infarction (n = 1), heart failure (n = 1), unstable angina (n = 10), and revascularization (n = 4). Clinical and stress echocardiographic variables previously related to adverse prognosis were entered in Cox regression analysis, and the predictors of impaired outcome were inducible ischemia during DSE (hazard ratio [HR], 2.97; 95% confidence interval [CI], 1.77 to 4.99; p < 0.001) and resting wall motion score index (WMSI) > 1.6 (HR, 1.68; 95% CI, 1.02 to 2.77; p = 0.04). After excluding revascularization procedures and considering only spontaneous events, the following predictors were found: ischemia during DSE (HR, 2.95; 95% CI, 2.78 to 3.12; p < 0.001) and resting WMSI > 1.6 (HR, 2.53; 95% CI, 1.30 to 4.93; p = 0.006). CONCLUSIONS: Inducible ischemia during DSE within 10 days after uncomplicated AMI predicts an impaired outcome in the elderly.

[MIBI-echocardiography with dobutamine: Significance of changes of contractility in patients with changes in perfusion]. / Ecocardiografía-MIBI con dobutamina: significado de las alteraciones de la contractilidad en pacientes con alteraciones de la perfusión.

BACKGROUND AND OBJECTIVES: In the presence of coronary artery disease and with an appropriate stressor, perfusion defects precede contractility abnormalities. Perfusion defects without contractility abnormalities may be due to the absence of ischemia or mild ischemia. Our purpose has been to compare the clinical characteristics, hemodynamic response and severity of perfusion defects in patients with coronary artery disease and perfusion defects with and without wall motion abnormalities during dobutamine infusion. PATIENTS AND METHODS: Eighty two patients with significant coronary artery disease demonstrated by angiography without previous myocardial infarction underwent dobutamine infusion (up to 40 mg/kg/min). Atropine was given when necessary. Stress scientigraphic MIBI-SPECT images were acquired 1 hour after peak stress and rest studies were obtained 24 hours after stress testing. The perfusion score was calculated by dividing the total uptake score between the number of segments affected. RESULTS: Among the 73 patients with perfusion defects, stress echocardiography was positive in 59 (Group A) and was negative in the remaining 14 (Group B). There were more hypertensive patients in Group A (33 vs 4; p = 0.04). There was no significant difference between the two groups with respect to other clinical characteristics. The peak rate-pressure product was similar in both groups (18.520 +/- 5.691 vs 18.680 +/- 5.329; p = NS). The development of electric abnormalities and angina was more common in Group A (42 vs 3, p < 0.001 and 33 vs 1; p < 0.001). Perfusion defects were not more extensive in Group A (abnormal segments 2.15 vs 2.21; p = NS) but they were more severe (segments with severe uptake reduction or no uptake 1.10 vs 0.28; p < 0.05; perfusion score 2.62 vs 2.21; p < 0.05). CONCLUSION: In patients with severe coronary artery disease and perfusion defects during dobutamine-MIBI-SPECT, the presence of wall motion abnormalities defines patients with more severe perfusion defects.

Selection of the optimal stress test for the diagnosis of coronary artery disease.

OBJECTIVE: To compare the value and limitations of exercise testing, dipyridamole echocardiography, dobutamine-atropine echocardiography, and MIBI-SPECT (technetium-99m methoxyisobutyl nitrile single photon emission computed tomography) during dobutamine infusion in the diagnosis of coronary artery disease. DESIGN: The performance of these four tests was assessed in random order on a consecutive cohort of patients. The presence or absence of coronary artery disease was confirmed by coronary angiography. SETTING: Two tertiary care and university centres. PATIENTS: 102 consecutive patients with chest pain and no previous history of coronary artery disease. Ten patients with left bundle branch block were excluded for further analysis of exercise testing and scintigraphy results. RESULTS: MIBI-SPECT was the most sensitive (87%) but the least specific test (70%). Exercise stress testing had a sensitivity of 66%, which increased to 80% when patients with inconclusive results were excluded. Dipyridamole and dobutamine echocardiography had similar sensitivity (81%, 78%) and specificity (94%, 88%). All four tests had similar accuracy and positive and negative predictive values. Agreement between the echocardiographic techniques was excellent (detection of coronary artery disease 87%, kappa = 0.72; regional analysis 93%, kappa = 0.72; diagnosis of the "culprit" vessel 95%, kappa = 0.92), and it was good between echocardiographic techniques and MIBI-SPECT (diagnosis of the culprit vessel 90%, kappa = 0.84 with dobutamine and 92%, kappa = 0.85 with dipyridamole). CONCLUSIONS: Exercise stress testing has a sensitivity comparable to other tests in patients capable of exercising and with no basal electrical abnormalities. The greatest sensitivity is offered by MIBI-SPECT and the greatest specificity is obtained with stress echocardiography. Redundant information is obtained with dipyridamole echocardiography, dobutamine echocardiography, and MIBI-SPECT.

[Echocardiography with dobutamine in hypertensive patients with chest pain]. / Ecocardiografía con dobutamina en pacientes hipertensos con dolor torácico.

INTRODUCTION: The exercise stress test shows limited diagnostic accuracy for the detection of coronary artery disease in hypertensive patients. Echocardiography with dobutamine is a useful tool in the assessment of coronary artery disease. PURPOSE: Our purpose has been to compare dobutamine stress echocardiography and exercise stress test for diagnosing coronary disease in hypertensive patients. MATERIAL AND METHODS: Dobutamine stress echocardiography (administered up to 40 micrograms/kg/min, and atropine when necessary), exercise stress test and coronary arteriography were performed on 74 hypertensive patients with chest pain and no previous history of coronary artery disease. RESULTS: Forty-eight (65%) patients underwent a diagnostic exercise stress test and 66 (89%) a diagnostic dobutamine stress echocardiography. Coronary artery disease (> or = 70% stenosis in, at least, one major vessel) was demonstrated in 28 (58%) patients who underwent a diagnostic exercise stress test, and in 39 (59%) patients who completed a dobutamine stress echocardiography. Sensitivity for exercise stress test was 82%, and 79% for dobutamine stress echocardiography (p = NS). Specificity was higher for dobutamine stress echocardiography (100% vs 60%; p < 0.005). CONCLUSIONS: Dobutamine stress echocardiography has high sensitivity and specificity for the detection of coronary artery disease in hypertensive patients. Dobutamine stress echocardiography has higher feasibility and specificity than exercise stress test in this group of patients.