The risk of stroke following CABG: one possible strategy to reduce it?

OBJECTIVE: Stroke remains a devastating complication of coronary artery bypass grafting (CABG): we evaluated whether a more aggressive diagnostic and therapeutic approach can reduce its incidence. METHODS: Between January 1998 and January 2002, 1388 consecutive patients underwent isolated on pump CABG with blood cardioplegia. Among the first 627 patients (Group A), Echo-Doppler study (DS) was performed only in selected patients (58) with history of cerebrovascular disease (CVD) and/or carotid bruit; in 761 patients (Group B), DS was performed routinely. Carotid endarterectomy (CEA) was performed in 45 patients in Group A associated to CABG during cardiopulmonary bypass (CPB) and in 90 patients in Group B under local anaesthesia before CABG. Brain CT scan was performed in all cases with postoperative neurological symptoms. RESULTS: The two groups were homogeneous for age, sex, associated diseases, history of CVD, number of graft and CPB time. There were no differences in terms of hospital mortality between Group A (22/627: 3.5%) and Group B (21/761: 2.75%); p=0.5. Postoperative stroke was observed in 24/627 (3.82%) patients of Group A and in 2/761 (0.26%) of Group B (p<0.001). Hospital mortality for stroke was higher in Group A (12/627: 1.91%) than in Group B (0/761; p<0.001) as well as the incidence of non-fatal stroke (Group A 12/627: 1.91% versus Group B 2/761: 0.26% p=0.006). CONCLUSIONS: Preoperative DS, performed in all cases of CABG, followed by CEA under local anaesthesia in patients with critical carotid stenosis reduces the incidence of postoperative stroke.

Increased QT dispersion and other repolarization abnormalities as a possible cause of electrical instability in isolated aortic stenosis.

The aim of our study was to analyze the ventricular repolarization phase in patients with isolated aortic stenosis (AS) in order to search for possible abnormalities that might contribute to an explanation of the electrical instability peculiar to this valve disease. We selected a population of 39 patients with isolated AS (25 M and 14 F, mean age 60+/-16 yrs). As controls we considered a group of 31 age-matched healthy subjects 20 M and 11 F, mean age 55+/-14 yrs, P=NS. Disease severity was assessed by echocardiography, calculating the maximum and mean pressure gradients max and mean PG) and the functional valve orifice area. Various electrocardiographic intervals (QT, QT'c, JT, JTc) and indices (QT and QTc dispersion were adopted for a detailed non-invasive evaluation of the ventricular repolarization. In patients with AS, M-QT (391+/-45 ms vs 362+/-25 ms, P=0.002), M=QTc (431+/-29 ms vs 412+/-19 ms, P=0.003), M-JT (290+/-41 ms vs 265+/-26 ms, P=0.003, M-JTc 331+/-29 ms vs 302+/-19 ms, P<0.001, QTD (67+/-34 ms vs 40+/-15 ms, P<0.001), QTcD (77+/-36 ms vs 52+/-23 ms, P<0.001) all resulted significantly greater than in controls. QTD and QTcD both resulted linearly related either to max PCi (r=0.388, P=0.018 and r=0.357, P=0.03) or to mean PG (r=0.513, P=0.004 and r=0.438, P=0.015), while M-JT and M-JTc turned out to be directly related only to mean PG (r=0.436, P=0.016 and r=0.483, P=0.007). Our findings suggest a prolonged duration of ventricular recovery and a greater dispersion of ventricular repolarization in patients with AS and might account for the electrical instability proper to this valve dysfunction. Besides, the existence of a linear direct relation between the severity of AS and the degree of inhomogeneity of left ventricular recovery, together with the correlation found among mean PCr and the total duration of the repolarization phase, expressed by the intervals JT and JTc, strongly suggest the hypothesis that in AS arrhythmogenic substrates development parallels the worsening of the valve defect.

Naltrexone treatment--the problem of patient acceptance.

Since the release of naltrexone for general use, we have offered it to approximately 300 narcotics-addicted patients admitted to our 4-week intensive treatment program at the Psychiatric Institute of Washington. Despite active persuasion, only 15 patients agreed to take the drug, and 11 started the outpatient phase of treatment. Only 3 of the 11 remained on naltrexone for more than 2 months. Negative local community attitudes toward all pharmacologic treatments, a strong focus on total abstinence by the recovering patient group, and self-elimination of poor candidates in this unselected population appear to be important factors in the poor acceptance of naltrexone.

Heart transplantation in patients with diuretic resistant heart failure.

Advanced heart failure is becoming an increasing cause of mortality and morbidity in a large number of patients. Heart transplantation is the treatment of choice for many selected patients in this group. According to the clinical status at the time of transplant, patients may have a different outcome related to the early survival, while the late results are similar and not affected by the patient's initial clinical status. All surviving patients showed recovery of kidney function as soon the cardiac output was restored to normal values. High urine output was present in a large number of patients in the early postoperative period. However, in severely ill patients with cardiac index <2.5 l/min/m2, diuretic resistance and mortality were higher.

Determinants and prognostic value of ischemic necrosis in early biopsies following heart transplant.

To evaluate the impact of early ischemic necrosis (IN) on the early and late outcome of heart transplantation, we reviewed our 11-year experience. Between January 1988 and June 1999, 207 heart transplants were performed in 205 patients (174 male and 31 female). Criteria for donor and recipient selection, and protocols for postoperative immunosuppression and rejection monitoring have remained unchanged over this period. Three different cardioplegic solutions were employed in graft preservation: St. Thomas Hospital solution in the earliest 31 cases (15%), University of Wisconsin solution in 96 cases (46.4%), and Celsior solution in the last 80 cases (38.6%). All patients who underwent at least one endomyocardial biopsy (176 patients) were divided into two groups according to the findings of IN within the early 3 postoperative months (group A, 49 patients with IN; group B, 127 patients without IN). The following variables were estimated in each group: donor and recipient age, ischemic time, type of cardioplegia, late mortality for cardiac causes, incidence of grade >2 rejection within the first 6 postoperative months, late incidence of grade >2 rejection, late incidence of NYHA class >II. No significant difference was found in any parameter between the two groups, except for the type of cardioplegic solution. A significantly higher incidence of ischemic necrosis in hearts preserved with St. Thomas solution was found (P < 0.001). Although pathology findings show that extracellular solutions carried a higher risk of early IN, no associated significant impairment in terms of late survival and event-free rate was observed in recipients with early IN.