Biomedical subjects

M Tamariz

Publications and source records attributed to M Tamariz.

5 recordsLinked to original sources

PubMed2002

Plasma vascular endothelial growth factor level is a predictor of the severity of postoperative capillary leak syndrome in neonates undergoing cardiopulmonary bypass.

Capillary leak syndrome (CLS), characterized by extravascular fluid accumulation and significant organ dysfunction, is a serious complication in children undergoing cardiopulmonary bypass (CPB). We examined the relationship between plasma vascular endothelial growth factor (VEGF) levels and severity of CLS. The kinetics of VEGF in the plasma of 11 neonates and 7 older children undergoing CPB were investigated, correlating plasma VEGF levels and CLS clinical presentation. The degree of postoperative CLS was quantified by measuring parameters of extracellular volume and end-organ dysfunction. A chest-wall soft-tissue-width index (CSTWI) was designed in order to standardize the extracellular fluid accumulation. Most CLS parameters were significantly more prominent in the neonatal patients. Low plasma VEFG levels (>35 pg/ml) were found in 3 neonatal control patients and all but, sample from the older group patient. The neonates had significantly higher preoperative VEGF plasma levels (684.4 +/- 559.1 pg/ml, P = 0.02), which decreased during the operation to levels below 35 pg/ml and increased again 24 h postoperatively to levels significantly higher than in the older patients (484 +/- 270.3 pg/ml, P = 0.001). Multilinear regression analysis found preoperative VEGF levels to independently correlate with CLS as represented by CSTWI (P < 0.01, r = 0.726). Both the occurrence of post-CPB CLS and plasma VEGF levels pre- and postoperatively were thus higher in neonates than in children. Plasma VEGF level is a predictor of the severity of postoperative CLS.

Capillary Leak Syndrome↗

PubMed2001

Renal dysfunction after cardiac surgery.

OBJECTIVE: To assess the causes and outcomes of patients with postcardiac surgery renal dysfunction. PATIENTS AND METHODS: A large cardiovascular data- base including pre-, peri- and postoperative serum creatinine concentrations from 2214 consecutive cardiac surgery patients was analyzed. RESULTS: Sixty-nine patients developed postoperative renal dysfunction, defined as at least a 15 mL/min decline in the creatinine clearance rate resulting in a value of less than 40 mL/min. These patients were significantly older, and had a higher incidence of previous cardiac surgery, diabetes, obesity, peripheral vascular disease, hypertension and poor ventricular function. Postoperatively, these patients had a higher occurrence of low output syndrome and myocardial infarction. Stepwise logistic regression predictors of postoperative renal dysfunction included the following: postoperative low output syndrome; repeat cardiac surgery; being older than 65 years; having diabetes; having poor left ventricular function; and having had valve surgery. Preoperative renal dysfunction (defined as a creatinine clearance of less than 40 mL/min) was not found to be one of the predictors. The mean creatinine concentrations of patients with mild postoperative renal dysfunction (defined as a creatinine concentration of less than 200 mmol/L on the fourth or fifth postoperative day) decreased significantly at the fifth postoperative day, while that of patients with severe postoperative renal dysfunction rose to a mean of 300 mmol/L six months postoperatively. The incidence of late dialysis (defined as a need for dialysis after postoperative day 10) approached 30% among patients with severe postoperative renal dysfunction and only 2% among patients with mild postoperative renal dysfunction. The early mortality rate (during the first postoperative month) was similar in both groups and approached 30%. CONCLUSIONS: Patients who develop postoperative renal dysfunction have a high mortality rate. Postoperative low cardiac output is the most important cause of postoperative renal dysfunction and, therefore, should be avoided. Patients with creatinine concentrations of less than 200 mmol/L at postoperative day 4 or 5 will probably resume normal renal function. Patients with creatinine concentrations of more than 200 mmol/L at days 4 and 5 have a 30% chance of needing long term dialysis.

Age Distribution↗

PubMed2000

Results of revascularization in patients with severe left ventricular dysfunction.

OBJECTIVE: In patients with coronary disease and poor left ventricular function, bypass grafting remains a surgical challenge. This study evaluates experience in 125 consecutive patients with ejection fraction less than 20% (study group). METHODS: Preoperative viability studies were not used for patient selection. Clinical data were prospectively collected. The average age of the study subjects was 59 +/- 9 years, and 112 (90%) were male. Most patients (108 [86%]) were in symptom class III or IV. Main indications for surgery included angina in 62 (50%), heart failure and angina in 36 (29%), heart failure in 9 (7%), ventricular arrhythmia in 2 (2%), and critical anatomy in 16 (13%). Significant mitral regurgitation was present in 48 (38%), and distal vessels were poorly visualized in 67 (54%). At surgery, temperature mapping guided an integrated approach to cold cardioplegia. Results in this group were compared with those obtained in case-matched control subjects receiving cardioplegia without temperature mapping (matched for age, sex, functional class, and urgency of operation). RESULTS: Hospital morbidity (intra-aortic balloon pump support) and mortality rates were significantly lower in the study group versus those of control subjects (15% vs 30%, P =. 004; and 4% vs 11%, P =.03, respectively). In study patients the 5-year actuarial survival was 72%. Among survivors, both anginal class and heart failure class improved significantly. By means of multivariate analysis, survival was adversely affected by older age, class IV symptoms, and poorly visualized distal vessels. CONCLUSIONS: These results support the use of coronary artery bypass grafting in patients with severe left ventricular dysfunction without case selection on the basis of viability studies or visibility of distal vessels. Low hospital morbidity and mortality rates have been achieved when temperature mapping guides cardioplegia. Symptoms are improved in most patients, and long-term survival is encouraging.

Case-Control Studies↗

PubMed1999

Current status of transmyocardial laser revascularization: review of the literature.

BACKGROUND: Transmyocardial laser revascularization (TMLR) is a new procedure for the treatment of angina pectoris in which high power laser energy is used to create channels in ischemic myocardium. OBJECTIVE: To describe in detail the historical, experimental and state-of-the-art studies regarding TMLR. DATA SOURCES: The English-language literature published from 1966 to 1998 was thorougly searched in MEDLINE. Further information regarding unpublished data was obtained on request. STUDY SELECTION: The most important experimental studies and randomized prospective clinical trials were examined. Additional papers were selected to provide a historical perspective and future prospects of TMLR. DATA SYNTHESIS: Although the results of TMLR in terms of angina relief are impressive, the procedure is associated with significant mortality and morbidity, and the results of objective cardiac perfusion measurements such as radionucleic perfusion scans and positron emission tomography are not conclusive. Furthermore, little information is available concerning the effect of this procedure on life expectancy. This article reviews the historical background of TMLR and possible mechanisms by which it may work, and discusses existing evidence for and against the procedure and how it may be applied in the future. CONCLUSIONS: At present, TMLR is potentially indicated for patients with severe angina that is refractory to medical therapy and who have contraindications for the more traditional therapies (coronary artery bypass grafting, percutaneous transluminal coronary angioplasty and transplantation). More data are needed to evaluate fully the indications for this procedure.

Angina Pectoris↗

PubMed1996

Risk factors for stroke in patients undergoing coronary artery bypass grafting.

OBJECTIVE: To determine predictors of stroke in patients undergoing first-time coronary bypass grafting, we prospectively collected data on 1631 consecutive patients. METHODS: Patients with a history of stroke and/or central nervous system symptoms (n = 134) and/or carotid bruits (n = 95) underwent carotid Doppler evaluation. Stenosis greater than 70% was considered significant. Patients with symptomatic disease or asymptomatic bilateral disease were referred for combined coronary bypass and carotid endarterectomy (n = 21). Patients with neurologic symptoms after the operation were assessed by a neurologist and underwent a computed tomographic scan. Events were classified as reversible transient ischemic attack, reversible ischemic neurologic deficit, or irreversible stroke. RESULTS: There were 19 strokes (1.2%) and 20 deaths (1.2%) in this series. In patients with carotid screening, risk of stroke increased with severity of carotid disease and ranged from 0% in patients without stenosis, to 3.2% (1/31) in those with greater than 70% stenosis, and to 27.3% (6/22) in those with carotid occlusion. By stepwise logistic regression analysis six variables were identified as risk factors for stroke. The most important predictor was carotid occlusion with or without contralateral stenosis (odds ratio = 28, 95% confidence interval (8,105). In this group, four of five strokes occurred on the occluded side. Other risk factors were presence of ascending aortic disease at the time of surgery (odds ratio = 12.8, confidence interval 3,48), perioperative myocardial infarction (odds ratio = 8.2, confidence interval 2,33), poor left ventricular function (odds ratio = 4.6, confidence interval 1,19), peripheral vascular disease (odds ratio = 3.2, confidence interval 1,9), and age > 60 years (odds ratio = 2.9, confidence interval 0.8,11). CONCLUSION: We conclude that risk factors for perioperative stroke in patients undergoing coronary artery bypass grafting are multiple. Carotid scanning in patients with neurologic symptoms or carotid bruits can identify patients at increased risk. Patients with carotid occlusion are at high risk for stroke on the occluded side.

Adult↗