Pascal A. Berdat

Transit-time flow measurement for detection of early graft failure during myocardial revascularization

BACKGROUND A low-flow situation in arterial and venous grafts has been associated with high rates of perioperative infarction and mortality. This study was designed to look at intraoperative graft flow and resistance in patients with coronary artery disease. METHODS Coronary artery bypass graft flow was measured in 46 patients. Transit-time flow was used for coronary flow measurements at rest as well as after maximal vasodilation with adenosine infusion. RESULTS Forty-three of the 46 patients showed normal internal mammary artery graft flow (>20 mL/min); 3 patients had no or minimal graft flow. Redoing the graft anastomosis in these 3 patients resulted in normalization of graft flow. The mean flow increased significantly after correction from 0.5 +/- 0.7 mL/min to 15.7 +/- 9.6 mL/min (p < 0.02). Conversely, vascular resistance decreased significantly from 138 +/- 10 to 4.8 +/- 1.8 Ohmv (p < 0.0001), as did the pulsatility index (from 146.9 +/- 95.7 to 3.4 +/- 1.8; p < 0.001). After correction, coronary flow reserve was 2.5 +/- 1.1. CONCLUSIONS Measurements of intraoperative flow and resistance as well as derived variables allow assessment of early graft function and thus help prevent graft failure and reduce perioperative infarction. Transit-time volume flow might be a simple tool for quality control in coronary bypass procedures.

Improvement of quality of life after surgery on the thoracic aorta: effect of antegrade cerebral perfusion and short duration of deep hypothermic circulatory arrest.

Background—We have recently demonstrated that the use of deep hypothermic circulatory arrest (DHCA) during surgery for acute type A aortic dissections or thoracic aortic aneurysms adversely affect mid-term quality of life (QoL). The aim of this study is to assess the impact of DHCA duration and the potential effects of antegrade cerebral perfusion (ACP) on mid-term QoL. Methods and Results—Between January 1994 and December 2002, 363 patients underwent surgery of the thoracic aorta with the use of DHCA at our institution. One hundred seventy-six (48.5%) presented with acute type A dissections and 187 (51.5%) presented with aortic aneurysms. ACP was used in 41 (11.3%) cases. All in-hospital data were assessed and a follow-up was performed in all survivors after 2.4±1.2 years. QoL was analyzed with the Short-Form 36 Health Survey Questionnaire (SF-36). In-hospital mortality was 8.6%. In comparison with patients having undergone DHCA <20 minutes, averaged QoL score was significantly decreased in patients with DHCA between 20 and 34 minutes (95.6±12.8 versus 81.9±15.7; P<0.01) and >35 minutes (61.8±18.3; P<0.01). Averaged QoL score was significantly better with the use of ACP, independently of the duration of DHCA. Conclusions—DHCA duration >20 minutes, and especially >35 minutes, adversely affects mid-term QoL in patients undergoing surgery of the thoracic aorta. The use of ACP, however, improved averaged QoL score at each time period and allows DHCA to be extended up to 30 minutes, without impairment in mid-term QoL.

Different techniques of distal aortic repair in acute type A dissection: impact on late aortic morphology and reoperation

OBJECTIVE To compare three different techniques of distal aortic repair in acute type A (de Bakey type I) aortic dissection and to evaluate their impact on the late morphology of the aortic arch and descending aorta and on the incidence of reoperation. METHODS From 65 patients operated on due to an acute type A aortic dissection between 1989 and 1993, 54 long-term survivors underwent clinical and radiologic follow-up examination after a mean postoperative interval of 62+/-16 months. The surgical techniques of distal aortic reconstruction included closed repair using Teflon felt reinforcement under moderate hypothermic cardiopulmonary bypass (n = 20) and open repair in deep hypothermic circulatory arrest using either Teflon felt reinforcement (n = 16) or gelatin-resorcin-formaldehyde (GRF) glue (n = 18) to readapt the dissected aortic layers. In all patients, MR imaging was performed on a 1.5-T whole body imaging system for the evaluation of the morphology and function of the heart, aorta and supraaortic branches. RESULTS Overall hospital mortality following surgical repair of type A aortic dissection was 15.4% during this time period. The highest rate of persistent false lumen perfusion (17/20, 85%) and presence of an intimal flap in the aortic arch (13/20, 65%) was observed in patients following closed repair of acute ascending aortic dissection, whereas the lowest rate of such findings was demonstrated in patients who had undergone open distal aortic repair using biological glue (false lumen perfusion 10/18, 55% and intimal flap in the arch 2/18, 11%). Redo-surgery was significantly reduced in the open repair group using GRF glue (1/18, 5.5%) as compared with the Teflon felt repair group (3/16, 18%) and the closed repair group (6/20, 30%). CONCLUSIONS In patients with acute type A dissection, open distal aortic repair using GRF-glue favourably influences both (1) the severity of late morphologic alterations in the downstream aorta and (2) the incidence of reoperation.

Large Area of the False Lumen Favors Secondary Dilatation of the Aorta After Acute Type A Aortic Dissection

Background—Since 1994 patients with acute aortic dissection type A (AADA) are followed-up in our outpatient clinic. Early diagnosis of secondary dilatation of the diseased aorta is crucial to reduce late mortality in these patients. Aim of the present study is to asses the impact of a large volume in the false lumen of the diseased downstream aorta on secondary dilatation. Methods and Results—134 patients of 264 patients who underwent surgery for AADA (between January 1994 and June 2003) are followed-up at our outpatient clinic since 1994. 84 patients (62.7%) fulfilled the inclusion criteria. Areas of the true and the false lumens of the aorta were analyzed and a logistic regression was calculated at 5 levels of the aorta for each patient. Patients were divided in 3 groups: group 1 included 34 patients (40.5%) without progression, group 2 had 34 patients (40.5%) with slight progression, and group 3 had 16 patients (19.0%) with important progression, requiring surgery in all patients. In 87.5% of the patients the area of the original lumen was <0% in group 3, compared with 11.8% in group 2 and 8.8% in group 1 in relation to the total area of the aorta 6 months after surgery (P<0.001). Conclusion—A large false lumen, with an area of the true lumen <30% 6 months after surgery, is the strongest predictor for secondary dilatation of the diseased downstream aorta.

Quality of life and specific problems after cardiac surgery in adolescents and adults with congenital heart diseases

Background Grown-ups with congenital heart disease (GUCH) constitute an increasing population. Some of them reach adulthood without intervention and may present with symptoms, some require first intervention or re-operation for various reasons. Although interventions become more and more frequent in these patients, limited knowledge exists on their quality of life (QoL). The aim of the present study was to analyze QoL in GUCH patients who underwent cardiac surgery after the age of 14 years. Design A total of 296 patients with a mean age of 35±16 years (range 14–72 years) were operated on at our institution between July 1987 and December 2000, mainly for atrial septal defect (ASD), outflow tract lesion, Marfan syndrome and coarctation. Early mortality was 3.4%. During follow-up QoL was assessed with the short form 36 health survey questionnaire (SF-36) and an additional questionnaire focused on medical and psychosocial aspects. Results were analyzed for the total collective and in relation to the underlying congenital heart disease (CHD). Results Quality of life was excellent and similar to an age- and gender-matched standard population, except in patients following repair of complete AV-canal. The main restrictions in this group were found in the emotional aspect (62.5±29.9) and physical role function (60.5±25.0) and reflected in limitations of daily activity. Conclusion Outcome and QoL in adolescents and adults with CHD is excellent and similar to that of an age- and gender-matched standard population. In the future special attention should be focused more strongly on medical follow-up and psychosocial problems in this increasing group of patients. Eur J Cardiovasc Prev Rehabil 12: 138–143

Pain treatment with a COX-2 inhibitor after coronary artery bypass operation: a randomized trial

BACKGROUND Adequate analgesic medication is mandatory after cardiac operations. Cyclooxygenase-2 inhibitors represent a new therapeutic option, acting primarily on the response to inflammation. METHODS We compared a cyclooxygenase-2 inhibitor (etodolac) with two traditional drugs: a nonselective cyclooxygenase inhibitor (diclofenac) and a weak opioid (tramadol) on postoperative pain and renal function in patients undergoing coronary artery bypass operations. Sixty consecutive patients were randomized into three groups: (1) group A patients who received tramadol; (2) group B patients who received diclofenac; and (3) group C patients who received etodolac. For measurement of analgesic effect, the visual analogue scale was assessed up to postoperative day 4. Creatinine-clearance was determined before and at the end of study medication, and serum creatinine and urea were monitored daily for renal effects. Study medication was given on postoperative days 2 and 3. Side effects and additional pain medication were recorded. RESULTS The visual analogue scale was lower in group C (p < 0.05) from postoperative days 2 to 4 and in group B (p < 0.05) from postoperative days 3 to 4 compared with group A. Amount of additional pain medication and incidence of side effects were significantly less in group C compared with group A. We observed a short-lasting elevation of serum creatinine and urea in groups B and C compared with group A (p < 0.05). CONCLUSIONS At the doses analyzed, etodolac and diclofenac produced better postoperative pain relief with less side-effects than tramadol. A short-lasting impairment of renal function was found in patients treated with etodolac and diclofenac.

Aprotinin reduces blood loss in off-pump coronary artery bypass (OPCAB) surgery

OBJECTIVE Effects of aprotinin in off-pump coronary artery bypass (OPCAB) surgery have not yet been described. This study analyses hemostasiologic changes and potential benefit in OPCAB patients treated with aprotinin. METHODS In a prospective, double-blind, randomized study 47 patients undergoing OPCAB surgery were investigated. Patients received either aprotinin (2 x 10(6) KIU loading dose and 0.5 x 10(6) KIU/h during surgery, n=22) or saline solution (control, n=25). Activated clotting time was adjusted to a target of 250 s intraoperatively. Blood samples were taken up to 18h postoperatively: complete hematologic and hemostasiologic parameters including fibrinopeptide A (FPA) and D-dimer in a subgroup of 31 patients were analyzed. Blood loss, blood transfusion and other clinical data were collected. RESULTS Both groups showed comparable demographic and intraoperative variables. Forty-one (87%) patients of the whole study group received aspirin within 7 days prior to surgery. Number of grafts per patient were comparable (2.9+/-1.0 [mean+/-SD] in the aprotinin group and 2.8+/-1.2 in control, P=0.83). Blood loss during the first 18 h in intensive care unit was significantly reduced in patients treated with aprotinin (median [25th-75th percentiles]: 500 [395-755] ml vs. 930 [800-1170] ml, P<0.001). Postoperatively only two patients (10%) in the aprotinin group received packed red blood cells, whereas eight (35%) in the control group (P=0.07). Perioperatively FPA levels reflecting thrombin generation were elevated in both groups. The increase in D-dimer levels after surgery was significantly inhibited in the aprotinin group (P<0.001). Early clinical outcome was similar in both groups. CONCLUSIONS Aprotinin significantly reduces blood loss in patients undergoing OPCAB surgery. Inhibition of enhanced fibrinolysis can be observed. FPA generation during and after OPCAB surgery seems not to be influenced by aprotinin.

Effects of deep hypothermic circulatory arrest on outcome after resection of ascending aortic aneurysm

BACKGROUND Aneurysm of the ascending aorta is a common finding especially in patients with aortic valve diseases. The aim of this study was to analyze early and midterm outcome in patients operated on for aneurysm of the ascending aorta with or without the use of deep hypothermic circulatory arrest (DHCA). METHODS Between January 1996 and December 2000, 133 of 410 patients with thoracic aortic pathology were operated on for an aortic aneurysm limited mainly to the ascending aorta. Early and midterm outcomes were assessed and quality of life (QOL) evaluated using the Short-Form 36 Health Survey Questionnaire (SF-36). RESULTS Sixty patients (group 1) were operated on with DHCA and 73 patients (group 2) without DHCA. In-hospital mortality was identical in both groups (9.6% versus 6.7%; p = not significant) whereas postoperative transient neurologic events were significantly more frequent in group 1 (6.7% versus 0%; p < 0.05). Midterm clinical outcome was not different between groups but QOL showed significant impairment in daily functional physical and emotional activity in group 1 patients compared with group 2 and an age-matched standard population. CONCLUSIONS The risk of transient neurologic complications is significantly increased with the use of DHCA and QOL is impaired without benefits in the long-term outcome especially among older patients.

Benefit to quality of life after Off-Pump versus On-Pump coronary bypass surgery

BACKGROUND Whether the clinical outcome of off-pump coronary artery bypass graft (OPCABG) surgery is superior to on-pump coronary artery bypass graft (CABG) surgery is still a matter of debate. However with the considerable reduction of mortality associated with CABG surgery in recent years, more subtle outcome indicators such as quality of life (QOL) become more important. The aim of this study was to compare midterm QOL after OPCABG with that after CABG procedures and with an age- and sex-matched standard population. METHODS Quality of life was assessed using the Short-Form 36 Health Survey Questionnaire for 504 consecutive patients after CABG (n = 438) and OPCABG (n = 66) operated on between June 1999 and November 2000 at our institution. RESULTS Except for single-vessel disease, which was more frequent in OPCABG compared with CABG procedures (13.6% versus 6.8%; p <0.01), the preoperative variables were similar. Median EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 3.2 +/- 1.3 in the CABG group compared with 3.0 +/- 0.8 in the OPCABG group (p = not significant). After a mean follow-up of 10.8 +/- 0.5 months physical role function (73.5 +/- 38.3 versus 45.3 +/- 41.6; p <0.01) and emotional role function (75.3 +/- 40.3 versus 61.0 +/- 43.9; p <0.01) were significantly better in OPCABG than in CABG patients. Compared with a standard population, OPCABG patients were significantly impaired in emotional role function and CABG patients in physical and emotional role function. CONCLUSIONS Midterm QOL after myocardial revascularization is fairly well preserved compared with an age- and sex-matched standard population and is superior after OPCABG compared with CABG. Whether this is only due to avoidance of cardiopulmonary bypass remains to be elucidated.

Early postoperative arrhythmias after open-heart procedures in children with congenital heart disease

Objective Evaluation of occurrence, clinical course, necessity of treatment, and outcome of early postoperative cardiac arrhythmias after open-heart surgery. Design Prospective study. Setting Tertiary pediatric intensive care and pediatric cardiology unit. Patients All consecutive pediatric patients undergoing cardiac surgery on cardiopulmonary bypass were studied for the occurrence of cardiac arrhythmias during the whole perioperative hospital stay. Measurements All patients had continuous electrocardiographic monitoring (with memory function) during the whole intensive care stay. A 24-hr Holter recording was done thereafter in patients with arrhythmias. Results Of 310 patients studied, 83 (27%) had postoperative arrhythmias. The occurrence rate was not different whether surgical access was by atriotomy or ventriculotomy (26% vs. 28%, respectively). Infants (39%) and cyanotic patients (36%) had a higher occurrence rate of arrhythmias (p < .05). Arrhythmias were more common after prolonged cardiopulmonary bypass time and with higher postoperative maximum troponin serum levels. In addition, patients with hemodynamically significant residual findings after correction had an increased occurrence rate of arrhythmias (18 of 43; 42%;p < .01). Of the 83 children with arrhythmias, 53 (64%) required specific antiarrhythmic treatment. The use of antiarrhythmic drugs was required in only 7 of these patients. Only one patient (1.2% of patients with arrhythmias) died from arrhythmia. No major complications resulting from arrhythmias occurred during the postoperative clinical course in the other patients. Conclusions Although they occur frequently, postoperative arrhythmias after open-heart procedures in children are associated with low morbidity and mortality.