A case of a periaortic lymphoma presenting with the features of descending thoracic aorta dissection.

We report the case of a 68-year-old male in whom an intrathoracic non-Hodgkin's lymphoma was diagnosed late after he presented with the clinical and radiological features of a descending aortic dissection due to penetrating ulcer. An endovascular stent was implanted in the descending aorta. At follow up, a CT scan showed the presence of a mediastinal mass thought to be a periaortic haematoma as a consequence of the endovascular stent implantation. A further CT scan showed an increase in size of the mediastinal mass encasing the whole descending aorta. A biopsy of the mass was performed which was shown to be non-Hodgkin's lymphoma. This is the first report of a penetrating ulcer of the descending aorta due to lymphoma, which probably caused the dissection.

Myocardial injury in hypertrophic hearts of patients undergoing aortic valve surgery using cold or warm blood cardioplegia.

OBJECTIVES: Myocardial protection techniques during cardiac surgery have been largely investigated in the clinical setting of coronary revascularisation. Few studies have been carried out on patients with left ventricular hypertrophy where the choice of delivery, and temperature of cardioplegia remain controversial. This study investigates metabolic changes and myocardial injury in hypertrophic hearts of patients undergoing aortic valve surgery using antegrade cold or warm blood cardioplegia. METHODS: Thirty-five patients were prospectively randomised to intermittent antegrade cold or warm blood cardioplegia. Left ventricular biopsies were collected at 5min following institution of cardiopulmonary bypass, 30min after cross-clamping the aorta and 20min after cross-clamp removal, and used to determine metabolic changes during surgery. Metabolites (adenine nucleotides, amino acids and lactate) were measured using high pressure liquid chromatography and enzymatic techniques. Postoperative myocardial troponin I release was used as a marker of myocardial injury. RESULTS: Ischaemic arrest was associated with significant increase in lactate and alanine/glutamate ratio only in the warm blood group. During reperfusion, alanine/glutamate ratio was higher than preischaemic levels in both groups, but the extent of the increase was considerably greater in the warm blood group. Troponin I release was markedly (P<0.05, Mean+/-SD) lower at 1, 24 and 48h postoperatively in the cold compared to the warm blood group (0.51+/-0.37, 0.37+/-0.22 and 0.27+/-0.19 vs. 0.75+/-0.42, 0.73+/-0.51 and 0.54+/-0.38ng/ml for cold vs. warm group, respectively). CONCLUSIONS: Cold blood cardioplegia is associated with less ischaemic stress and myocardial injury compared to warm blood cardioplegia in patients with aortic stenosis undergoing valve replacement surgery. Both cardioplegic techniques, however, confer sub-optimal myocardial protection.

Inflammatory response after coronary revascularization with or without cardiopulmonary bypass.

BACKGROUND: We sought to investigate the effect of multiple coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass (CPB) on the perioperative inflammatory response. METHODS: Sixty patients undergoing CABG were randomly assigned to one of two groups: (A) on pump with conventional CPB and cardioplegic arrest, and (B) off pump on the beating heart. Serum samples were collected for estimation of neutrophil elastase, interleukin 8 (IL-8), C3a, and C5a preoperatively and at 1, 4, 12, and 24 hours postoperatively. Furthermore, white blood cell (WBC), neutrophil, and monocyte counts were carried out preoperatively and at 1, 12, 36 and 60 hours postoperatively. Overall incidence of infection and perioperative clinical outcome were also recorded. RESULTS: The groups were similar in terms of age, weight, gender ratio, extent of coronary disease, left ventricular function, and number of grafts per patient. Neutrophil elastase concentration peaked early after CPB in the on-pump group, with a decline with time. Repeated-measures analysis of variance between groups and comparisons at each time point (modified Bonferroni) showed elastase concentrations were significantly higher in the on-pump than the off-pump group (both p < 0.0001). IL-8 increased significantly after surgery in the on-pump group, with no decline during the observation period (p = 0.01 vs off pump). C3a and C5a rose early after surgery in both groups when compared with baseline values. Postoperative WBC, neutrophil, and monocyte counts were significantly higher in the on-pump than the off-pump group (p < 0.01). Finally, the incidence of postoperative overall infections was significantly higher in the on-pump group (p < 0.0001 vs off pump). CONCLUSIONS: CABG on the beating heart is associated with a significant reduction in inflammatory response and postoperative infection when compared with conventional revascularization with CPB and cardioplegic arrest.

Evaluation of myocardial metabolism and function during beating heart coronary surgery.

Coronary artery bypass surgery on the beating heart either via a left anterior small thoracotomy (LAST) or a median sternotomy is becoming increasing popular world-wide. Concern still remains about the potential for a temporary regional myocardial ischaemia associated with the stabilisation and occlusion of the coronary during construction of the anastomosis. This review summarises the results of a series of studies intended to evaluate the effect of beating heart coronary revascularization on myocardial function, myocardial tissue injury and clinical outcome.

Nonembolic predictors of stroke risk in coronary artery bypass patients.

The aim of this study was to identify and stratify the most important nonembolic risk factors for stroke after coronary bypass grafting. From June 1994 to June 1997 a series of 1532 patients (pts) underwent isolated myocardial revascularization on cardiopulmonary bypass (CPB). A retrospective chart review selected 1417 pts in whom the presence of aortic calcification or left ventricular mural thrombi was not detectable by echocardiogram, angiogram, and intraoperative records. Univariate and multivariate analyses were conducted to identify nonembolic variables independently correlated to postoperative stroke. A predictive model of stroke probability was then constructed by means of a mathematic method with the variables selected from logistic regression analyses. The global incidence of stroke was 1.8%. Univariate analysis revealed that, among 29 preoperative and operative variables, age, vasculopathy, emergency operation, previous cerebrovascular accident (CVA), CPB, and aortic cross-clamping times were factors strongly associated with postoperative stroke (p < 0.01). A first logistic regression analysis (LRA) selected as independent predicting variables (p < 0.05) age [odds ratio (OR) 1.07/year], vasculopathy (OR 4), previous CVA (OR 7.2), CPB time (OR 1/year), and emergency operation (OR 4.2). In a second stepwise LRA, age and CPB time were subdivided into cohorts as follows: age 65 but < 75 years, >/= 75 years; CPB time 120 but < 180 minutes, >/= 180 minutes. Both age >/= 75 years (p = 0.024; OR 3.3) and CPB time >/= 180 minutes (p = 0.002; OR 4.2), were found to be predictors of postoperative neurologic damage. Finally, a probability table of stroke risk was obtained with the logistic regression coefficients. A lower stroke probability (0.7%) was calculated in the absence of risk variables and a higher one in the presence of all of them (83.3%). Between these extremes, a total of 158 combinations of stroke probabilities were obtained. We concluded that previous CVA, vasculopathy, emergency operation, and age > 75 years are variously associated with a high risk of nonembolic stroke after myocardial revascularization. A duration of CPB longer than 3 hours strongly increases the probability of neurologic damage in the presence of the aforementioned variables.

Economic outcome of off-pump coronary artery bypass surgery: a prospective randomized study.

BACKGROUND: Emphasis on cost containment in coronary artery bypass surgery is becoming increasingly important in modern hospital management. The revival of interest in off-pump (beating heart) coronary artery bypass surgery may influence the economic outcome. This study examines these effects. METHODS: Two hundred patients undergoing first-time coronary artery bypass surgery were prospectively randomized to either conventional cardiopulmonary bypass and cardioplegic arrest or off-pump surgery. Variable and fixed direct costs were obtained for each group during operative and postoperative care. The data were analyzed using parametric methods. RESULTS: There was no difference between the groups with respect to pre- and intraoperative patient variables. Off-pump surgery was significantly less costly than conventional on-pump surgery with respect to operating materials, bed occupancy, and transfusion requirements (total mean cost per patient: on pump, $3,731.6+/-1,169.7 vs off-pump, $2,615.13+/-953.6; p < 0.001). Morbidity was significantly higher in the on-pump group, which was reflected in an increased cost. CONCLUSIONS: Off-pump revascularization offers a safe, cost-effective alternative to conventional coronary revascularization with cardiopulmonary bypass and cardioplegic arrest.

Video-assisted minimally invasive coronary bypass surgery without cardiopulmonary bypass.

BACKGROUND: There is a growing interest in cardiac surgery towards minimally invasive approach to coronary bypass operations without cardiopulmonary bypass. PATIENTS AND METHODS: From March 1995 to March 1997, 41 patients underwent a single left internal mammary artery (LIMA) to the left anterior descending artery (LAD) coronary grafting without cardiopulmonary bypass through a small left anterior thoracotomy (MIDCABG). The mean age was 61.2+/-8.7 years (range 43-77 years), 28 patients. were male (68.2%) and the redo rate was 4.8% (2/41). In all patients the coronary artery disease involved the LAD, which was occluded in seven patients (17.1%). Thirty-eight patients (96.2%) selected for MIDCABG had a monovascular disease on LAD not suitable for percutaneous coronary angioplasty; two (4.8%) a bivascular disease, and one (2.4%) a trivascular disease. Skin incision was performed in the 4th anterior intercostal space from the left parasternal line for a 10.5 cm length on average. The LIMA harvesting was partially video-assisted by thoracoscopy. RESULTS: The LAD temporary occlusion was achieved with two double 5/0 polypropilene round-LAD sutures. The mean LAD ischemic time was 22+/-8 min (range 4-35 min). No thoracotomy procedure was changed into a sternotomy approach. We had one (2.4%) perioperative AMI; two patients (4.8%) were reoperated for bleeding. All patients underwent a postoperative angiographic reinvestigation within 1 month after surgery. All anastomoses were perfectly patent but two (4.8%). One patient was reoperated via a sternotomy access recycling the LIMA graft, the other one underwent successful PTCA. All patients also underwent an early and mid-term (6 months after surgery) echo-Doppler study of the LIMA flow and patency. At follow-up, performed at a mean of 8.7 months (range 1-23) after discharge, all patients were alive; no one experienced recurrence of angina. All patients also performed a mid-term negative treadmill stress test. CONCLUSIONS: MIDCABG is, in selected patients, reliable and safe, and offers encouraging early and mid-term clinical results.

Which variable of stenosis severity best describes the significance of an isolated left anterior descending coronary artery lesion? Correlation between quantitative coronary angiography, intracoronary Doppler measurements and high dose dipyridamole echocardiography.

OBJECTIVES: This study sought to investigate the angiographic or intracoronary Doppler variables of stenosis severity that best correlate with the results of dipyridamole echocardiography. BACKGROUND: Quantitative coronary angiography and intracoronary Doppler flow velocity assessments are the commonly used techniques for the objective identification of significant coronary artery stenosis. METHODS: Thirty patients with an isolated lesion of the left anterior descending coronary artery (LAD) were studied by means of on-line quantitative coronary arteriography, intracoronary Doppler flow velocity measurements and dipyridamole echocardiography 6 months after percutaneous transluminal coronary angioplasty. The quantitative arteriographic analyses were performed on-line; post-stenotic Doppler flow velocities were measured at baseline and after adenosine infusion. Angiographic and Doppler measurements were compared with the corresponding dipyridamole echocardiographic data and analyzed by discriminant analysis. RESULTS: The dipyridamole echocardiographic response was positive in 11 patients (37%). The best cutoff values for predicting an abnormal echocardiographic response were 1) stenotic flow reserve of 2.8 (p = 0.0001); 2) 59% diameter stenosis (p = 0.0001); 3) minimal lumen diameter of 1.35 mm (p = 0.001); 4) coronary flow reserve of 2.0 (p = 0.0002); and 5) maximal peak velocity of 60 cm/s during hyperemia (p = 0.04). Multivariate analysis identified stenotic flow reserve as the only independent predictor of ischemia during dipyridamole echocardiography. CONCLUSIONS: Stenotic flow reserve is the variable that best describes the functional significance of an isolated LAD lesion, and a value of 2.8 is the best predictor of a positive dipyridamole echocardiographic response. Furthermore, angiographic variables of stenosis severity relate to echocardiographic test results better than intracoronary Doppler variables.

Mid-term follow-up of 183 arterial myocardial revascularization procedures.

OBJECTIVE: To evaluate the mid-term results of complete arterial myocardial revascularization performed with arterial conduits. METHODS: From July 1987 to December 1994, 183 patients underwent a myocardial revascularization procedure with the use of at least two arterial grafts (IMAs, rGEA, IEA) at our institute. Their mean age was 56 +/- 8.7 years, the redo-operation rate was 16.9% (31/183), two-vessel disease was present in 61 patients (33.3%), three-vessel disease in 122 (66.7%). RESULTS: The LIMA was used in 179 patients (97.8%), the RIMA in 116 (63.4%), the rGEA in 66 (36.1%) and the IEA in 41 (22.4%). In-hospital mortality was 1.1% (2/183), while the perioperative myocardial infarction (MI) rate was 2.2% (4/183). The angiographic restudy, performed on 87 (47.5%) patients during the early postoperative period (median 38 days) showed the following grafts patency rates: LIMA 98.8 (86/87), RIMA 97.1 (34/35), IEA 85.7 (24/28), rGEA 97.05 (33/34) and saphenous vein 90.9% (10/11). The median follow-up was 35 months. Kaplan-Meier survival was 96 +/- 2% at 3 and 5 years, freedom from angina 94 +/- 2% at 3 years and 91 +/- 3% at 5 years, while the Kaplan-Meier freedom from cardiac events was 90 +/- 3% at 3 years and 88 +/- 3% at 5 years. Cox regression analysis identified perioperative MI (P = 0.03, relative risk 3.6) as the only prognostic factor for mortality at follow-up. With regards to recurrence of angina, multivariate analysis has shown that incremental risk factors for the return of angina are redo-operation (P < 0.01, relative risk 2.7) and the persistence of hypertension after surgery (P < 0.01; relative risk 3.2), while the use of the RIMA in the operation has emerged as a protective factor (P = 0.02; relative risk 0.43). Finally, only redo-operation (P < 0.01; relative risk 2.3), has emerged as a predictor of cardiac complications. CONCLUSION: Myocardial revascularization with at least two arterial grafts can be performed with very low perioperative morbidity and mortality and good mid-term follow-up. The mid-term results of arterial myocardial revascularization are less favourable in cases of redo-operations or when the RIMA is not used.

Role of right gastroepiploic artery in myocardial revascularization with arterial grafts.

Between July 1990 and December 1992. 112 patients underwent myocardial revascularization with arterial grafts in the Department of Cardiac Surgery, University of Milan. Monovascular patients were excluded from the study. The right gastroepiploic artery was used in 44 patients (39.3%); mean age was 54.3 years and reoperation rate 18.2%. Of the 44 patients, previous myocardial infarction had occurred in 25 (57%). Emergency operation was performed in one case (2%). Mean left ventricular shortening fraction was 36% and mean ejection fraction 58.6%. Coronary artery disease was bivascular in 10 patients (23%) and trivascular in 34 (77%). The arterial revascularization in patients with gastroepiploic artery was performed using a left internal thoracic artery graft in all 44 patients; the right internal thoracic artery was used in 18 (41%) and the inferior epigastric artery in two (4%). The sites of gastroepiploic artery grafting were 55% posterior descending, 16% right coronary artery, 11% posterolateral branch, 14% circumflex and in 4% posterior descending and posterolateral as sequential graft. No patient died; postoperative myocardial infarction rate was 4%. No complications related to gastroepiploic artery utilization were noted. Forty-three (98%) of the gastroepiploic artery group underwent graft reinvestigation: the arteries were correctly visualized in 41 patients (95%) and were patent in 39 cases and stenotic in two. A mid-term postoperative stress test (mean 17.4 months) was performed in 91% of patients. Normal limits were found in 37 patients (92.5%) and an abnormal stress test result in three (7.5%). The contemporary follow-up showed no deaths or myocardial infarctions. Three patients (7%) had recurrent angina. The role of gastroepiploic artery in arterial revascularization has become fundamental, especially, it is believed, for the posterior or posterolateral left ventricular wall. The present data show the patients to be clinically and functionally well 1 year after operation.