Surgical repair of left ventricular free-wall rupture complicating acute myocardial infarction: a single-center 30 years of experience.

Background: Left ventricular free-wall rupture (LVFWR) is a catastrophic complication of acute myocardial infarction (AMI). Historically, cardiac surgery is considered the treatment of choice. However, because of the rarity of this entity, little is known regarding the efficacy and safety of surgical treatment for post-infarction LVFWR. The aim of this study was to report a single-center experience in this field over a period of 30 years. Methods: Patients who developed LVFWR following AMI and underwent surgical repair at our Institution from January 1990 to December 2019 were considered. The primary end-point was in-hospital morality rate; secondary outcomes were long-term survival and postoperative complications. Multivariate analysis was carried out by constructing a logistic regression model to identify risk factors for early mortality. Results: A total of 35 patients were enrolled in this study. The mean age was 68.9 years; 65.7% were male. The oozing type of LVFWR was encountered in 29 individuals, and the blowout type in 6 subjects. Sutured repair was used in 77.1% of patients, and sutureless repair in the remaining cases. The in-hospital mortality rate was 28.6%. Low cardiac output syndrome was the main cause of postoperative death. Multivariable analysis identified age >75 years at operation, preoperative cardiac arrest, concurrent ventricular septal rupture (VSR) as independent predictors of in-hospital death. Follow-up was complete in 100% of patients who survived surgery (mean follow-up: 9.3 ± 7.8 years); among the survivors, 16 patients died during the follow-up with a 3-year and 12-year overall survival rate of 82.5% and 55.2%, respectively. Conclusions: Surgical treatment of LVFWR following AMI is possible with acceptable in-hospital mortality and excellent long-term results. Advanced age, concurrent VSR and cardiac arrest at presentation are independent risk factors of poor early outcome.

Early paravalvular leak after conventional mitral valve replacement: A single-center analysis.

INTRODUCTION: Paravalvular leak (PVL) is a well-recognized complication after mitral valve replacement (MVR). However, there are only a few studies analyzing leak occurrence and postoperative results after surgical MVR. The aim of this study was to assess the rate and determinants of early mitral PVL and to evaluate the impact on survival. METHODS: We performed a retrospective analysis involving patients who underwent MVR from January 2012 to December 2019 at our Institution. Postoperative transthoracic echocardiography evaluation was done for all subjects before hospital discharge. Multivariable analysis was carried out by constructing a logistic regression model to identify predictors for PVL occurrence. RESULTS: Four hundred ninety-four patients were enrolled. Operative mortality was 4.9%. Early mitral PVL was found in 16 patients (3.2%); the majority were mild (75%). Leaks occurred more frequently along the posterior segment of the mitral valve annulus (62.5%). Only one individual with moderate-to-severe PVL underwent reoperation during the same hospital admission. Multivariable analysis revealed that preoperative diagnosis of infective endocarditis was the only factor associated with early leak after MVR (odds ratio: 4.96; 95% confidence interval: 1.45-16.99; p = .011). Overall mortality at follow-up (mean follow-up time: 4.7 [SD: 2.5] years) was 19.6% and favored patients without early mitral PVL. CONCLUSION: The incidence of early PVL after MVR is low. PVL is usually mild and develop more frequently along the posterior segment of the mitral valve annulus. Preoperative diagnosis of infective endocarditis increases the risk of PVL formation.

Surgical treatment of primary cardiac tumors in the contemporary era: A single-centre analysis.

BACKGROUND: Primary cardiac tumors (PCT) are rare lesions but have the potential to cause significant morbidity if not timely treated. We reviewed our single-center experience in the surgical treatment of PCT with a focus on the long-term outcome. METHODS: From 2001 to 2020, 57 consecutive patients underwent surgical resection of PCT at our Institution. Data including the demographic characteristics, tumor histology, surgical procedure, and postoperative outcomes were collected and analyzed. RESULTS: Mean age at presentation was 63.6 ± 11.2 years, and 33 (57.9%) of the patients were female. A total of 55 (96.5%) subjects were diagnosed with benign cardiac tumor, while the remaining had malignant tumors. The most common histopathological type was myxoma. All patients survived to hospital discharge. Main postoperative complications were: acute kidney injury (n = 3), sepsis (n = 3), and stroke (n = 2). Mean follow-up time was 9 ± 5.9 years. Long-term mortality was 22.8% (13/57). No tumor recurrence was observed among survivors. There was a significant relationship between mortality and pathological characteristics of the tumor, and myxomas had higher survival rates. CONCLUSION: Surgical treatment of PCT is a safe and highly effective strategy associated with excellent short-term outcomes. Long-term survival remains poor for primary malignant tumors of the heart.

Ascending aortic aneurysm repair in the setting of Tako-tsubo cardiomyopathy.

Tako-tsubo cardiomyopathy (TC) is characterized by acute but transient ventricular dysfunction without obstructive coronary artery disease, generally precipitated by emotional and physical triggers. We describe this syndrome in a 76-year-old woman who was admitted with thoracic pain secondary to TC as shown by echocardiographic assessment, with a concurrent diagnosis of giant ascending aortic aneurism. Surgical intervention was delayed to allow ventricular recovery and then to perform ascending aorta replacement. An individualized perioperative approach was applied to avoid a possible TC recurrence with an uneventful postoperative course.

Hyperlactatemia during cardiopulmonary bypass: risk factors and impact on surgical results with a focus on the long-term outcome.

INTRODUCTION: Lactate, a product of anaerobic metabolism, is a biomarker and indicator for tissue hypoperfusion and oxygen debt. An elevated blood lactate level has been associated with poor outcome in many clinical conditions, including cardiac surgery. Nevertheless, debate exists regarding which blood lactate concentration is most indicative of poor outcomes. We evaluate the impact of hyperlactatemia, defined as a peak arterial blood concentration ⩾2.0 mmol/L during cardiopulmonary bypass, on surgical results with a focus on long-term outcome. METHODS: We reviewed 1,099 consecutive adult patients who underwent cardiac surgery on pump. The patients were divided into two groups based on the presence or not of hyperlactatemia. Pre- and intraoperative risk factors for hyperlactatemia were identified, and the postoperative outcome of patients with or without hyperlactatemia was compared. RESULTS: Hyperlactatemia was present in 372 patients (33.8%). Factors independently associated with hyperlactatemia were urgent/emergency procedure, cardiopulmonary bypass duration and aortic cross-clamp time. Patients with hyperlactatemia had significantly higher rate of prolonged mechanical ventilation time, in-hospital stay and requirement of inotropes and intra-aortic balloon pump support (p < 0.001). Operative (30-day) mortality was higher in the group of patients with hyperlactatemia (7.8% vs. 1.1%; p < 0.001). Kaplan-Meier curve showed worse long-term survival (mean follow-up: 4.02 ± 1.58 years) in patients with hyperlactatemia. CONCLUSION: Hyperlactatemia during cardiopulmonary bypass has a significant association with postoperative morbidity and mortality. Correction of risk factors for hyperlactatemia, together with prompt detection and correction of this condition, may control complications and improve outcome.

Early Aortic Paravalvular Leak After Conventional Cardiac Valve Surgery: A Single-Center Experience.

BACKGROUND: Paravalvular leak (PVL) is a well-known complication after aortic valve replacement (AVR). Although some studies have described the incidence of postoperative aortic PVL, there are conflicting data about the predictive factors and a paucity of evidence regarding their time course and impact on survival. METHODS: Data were collected from patients who underwent surgical AVR at Circolo Hospital in Varese, Italy from January 2014 to December 2017. A transthoracic echocardiogram (TTE) was performed in all patients before hospital discharge. Additionally, a second TTE was obtained during postoperative follow-up in subjects with early aortic PVL. RESULTS: A total of 514 patients were enrolled in the study. At hospital discharge, aortic PVL was present in 60 patients (11.7%); the majority (78.3%) of the PVLs were mild. Multivariate logistic regression analysis identified smaller body surface area, female sex, and operating surgeon as the strongest predictors of early aortic PVL. Follow-up TTE was available for 50 patients (83.3%). Median time from the date of surgery to follow-up TTE was 2.2 years (0.4 to 4 years). Most aortic PVLs remained unchanged (50%) or disappeared (36%) over time. Only 2 patients (4%) had a progression of the leak. Overall, mortality was 8.4% (43 of 514). Survival was negatively affected by the presence of residual, mild to moderate, or moderate aortic PVL. CONCLUSIONS: Aortic PVL is not uncommon after standard AVR. Operating surgeon, smaller body surface area, and female sex are risk factors for the development of this complication. These leaks are usually mild and generally have a benign course. However, the presence of mild to moderate or more severe aortic PVL may influence postoperative survival.

Safety and efficacy of biatrial vs left atrial surgical ablation during concomitant cardiac surgery: A meta-analysis of clinical studies with a focus on the causes of pacemaker implantation.

INTRODUCTION: The latest STS guidelines recommend concomitant atrial fibrillation (AF) ablation not only during mitral surgery (Class IA) but also during other-than-mitral cardiac surgery procedures (Class IB) in patients with preoperative AF. Conventional Cox-Maze III/IV procedures are performed on both atria (BA), but several studies reported excellent results with left atrial only (LA) ablations: the scope of this study is to compare the safety and efficacy of BA vs LA approach. METHODS AND RESULTS: Pubmed, Scopus, and WOS were searched from inception to November 2018: 28 studies including 7065 patients and comparing the performance of BA vs LA approaches were identified: of these, 16 (57.1%) enrolled exclusively patients with non-paroxysmal AF forms, 10 (35.7%) focused on mitral surgery as main procedure, and 16 (57.1%) regarded patients undergone Cox-Maze with radiofrequency. The 6- and 12-months prevalence of sinus rhythm were higher in the BA group (OR, 1.37, CI, 1.09-1.73, P = .008 and OR, 1.37, CI, 0.99-1.88, P = .05 respectively). Permanent pacemaker (PPM) implantation (OR, 1.85, CI, 1.38-2.49, P < .0001) and reopening for bleeding (OR, 1.70, CI, 1.05-2.75, P = .03) were higher in the BA group. Among patients undergone PPM implantation, BA group had a significantly higher risk of sinoatrial node dysfunction (OR, 3.01, CI, 1.49-6.07, P = .002). CONCLUSIONS: Concomitant BA ablation appears superior to LA ablation in terms of efficacy but is associated with a higher risk of bleeding and of PPM implantation, more frequently due to sinoatrial node dysfunction. LA approach should be preferable in patients with a higher risk of bleeding or with perioperative risk factors for PPM implantation.

Non-inferiority randomized trials, an issue between science and ethics: the case of the SYNTAX study.

Non-inferiority trials are questionable when death and serious complications are included among outcomes. The term itself "non-inferiority" is misleading, since such a study would not demonstrate that a new treatment is non-inferior to a control treatment, but simply that the inferiority would not reach a pre-specified level, deemed as acceptable by the designers of the trial. Group cross-over, assay-sensitivity and the need of a placebo arm are major issues for the reliability of non-inferiority trials. The SYNTAX trial for severe coronary artery disease was designed on a non-inferiority margin of 6.6%. In this paper we show that the SYNTAX designers were ready to accept up to 30% higher rate of death and major adverse events to claim the non-inferiority of percutaneous coronary intervention versus coronary artery bypass grafting. Eventually the SYNTAX study failed because percutaneous patients sustained an even higher rate of adverse events. We propose major caution in performing non-inferiority randomized trials.

Myocardial metabolism assessed by microdialysis: a prospective randomized study in on- and off-pump coronary bypass surgery.

OBJECTIVE: The aim of the study was to compare energetic metabolism in the myocardium during coronary surgery with and without cardiopulmonary bypass by means of microdialysis. METHODS: Twenty-six low-risk patients were prospectively randomized to off-pump versus on-pump surgery. Microdialysis was used to sample myocardial interstitial fluid during and for 23 hours after surgery. RESULTS: Preoperative characteristics and clinical outcome were similar in both groups. Blood glucose and lactate did not differ between groups throughout the observation time. During surgery, intramyocardial levels of glucose, pyruvate and urea were unaffected in off-pump patients, while the same substances significantly decreased (p<0.05) in on-pump patients during cardioplegic arrest, and increased during reperfusion. Interstitial lactate levels were higher during off-pump surgery (p<0.05). From 3 to 15 hours after surgery, intramyocardial concentrations of glucose, urea and lactate were higher in off-pump patients (p<0.001), while pyruvate was higher in on-pump patients (p<0.01). Intramyocardial lactate/pyruvate ratio never differed between groups. Postoperatively, cumulative blood release of troponin-T was significantly higher in the on-pump group (p<0.005). CONCLUSIONS: Microdialysis could demonstrate significant differences in energetic metabolism between the two groups. Our data confirm and might help in explaining the lower release of myocardial ischemic markers after off-pump surgery.

Myocardial release of FKBP12 and increased production of FKBP12.6 in ischemia and reperfusion experimental models.

BACKGROUND: Coronary artery occlusion and reperfusion may trigger reversible and irreversible ischemic and reperfusion injury. The primary aim of this study was to evaluate protein release into the myocardium in a porcine model during ischemia and reperfusion to search for clarifying models for reperfusion injury and secondarily to investigate release and production of the immunophilins FKBP12/12.6 in this model and in cell cultures. METHODS: In a porcine model local myocardial ischemia was induced during 45min followed by 120min of reperfusion. Microdialysis samples from ischemic and non-ischemic areas were analyzed with surface-enhanced laser desorption ionization (SELDI) mass spectrometry (MS) and Western blotting (WB). Myocardial biopsies from areas at risk and control areas were analyzed with reverse transcription polymerase chain reaction (RT-PCR). Myocardial cell cultures from mice (HL-1 cells) were exposed to hypoxia and then analyzed with WB and RT-PCR. RESULTS: FK binding protein12 (FKBP12), ubiquitin and myoglobin were identified as being released during ischemia and reperfusion in microdialysates. RT-PCR analysis on the biopsies after ischemia revealed a non-significant increase in mRNA expression of FKBP12 and a significant increase in mRNA expression of FKBP12.6. Lysates from HL-1 cells exposed to hypoxia demonstrated increase of FKBP12 and a significant increase in mRNA expression of FKBP12.6. CONCLUSION: In a myocardial ischemic-reperfusion porcine model as well as in hypoxic HL-1 cells, release of FKBP12 and increased production of FKBP12.6 was demonstrated. The findings indicate important mechanisms related to these immunophilins in the reaction to ischemia/hypoxia and reperfusion in the heart.

Transthoracic echocardiography is adequate for the diagnosis of right coronary artery aneurysms.

Coronary artery aneurysms (CAA) are rare but potentially fatal pathologies. This case was referred to our Unit after occasional echocardiographic finding of an intracardiac mass. A new detailed transthoracic echocardiogram was decisive for a diagnosis of a large CAA of the right coronary artery, compressing and dislocating the right atrium. Transesophageal echocardiography was not performed because of the data obtained. The diagnosis was confirmed by cardiac catheterization. The patient was managed with a surgical procedure.

Functional recovery of chronic ischemic myocardium after surgical revascularization correlates with magnitude of oxidative metabolism.

BACKGROUND: The purpose of this study was to validate myocardial microdialysis measurements in patients after myocardial infarction with or without associated postoperative functional recovery in order to develop a highly sensitive tool for real-time in vivo detection of microcellular disorder during cardiac operations. METHODS: In 20 patients undergoing coronary artery bypass grafting, microdialysis catheters were implanted into scar or hibernating segments detected by means of magnetic resonance imaging, and into a vital area of the right ventricle (control). Myocardial glucose, lactate and pyruvate were analyzed perioperatively. Myocardial ethanol washout was measured as a sign of recovered local blood flow. RESULTS: After surgical revascularization, improvement of wall motion was found in all hibernating segments compared to the scar segments paralleling an increased glucose delivery to the tissue and increased myocardial tissue flow. The myocardial glucose/lactate ratio and pyruvate also showed significantly higher values. Microdialytic measurements of the viable segments were comparable with those of the right ventricle. CONCLUSIONS: Our results indicate that microdialysis measurements parallel magnetic resonance imaging findings in patients with revascularization of chronic ischemic myocardium with dyskinetic segments. The metabolism of those segments is characterized by a significantly increased tissue flow, an increased utilization of glucose and a better oxidative nutrition.

Evaluation of myocardial metabolism with microdialysis during bypass surgery with cold blood- or Calafiore cardioplegia.

BACKGROUND: For the first time, microdialysis was used to investigate in vivo and online the myocardial metabolism during and after cardiac surgery in patients treated with two different methods of myocardial protection. METHODS: Thirty patients underwent standard CABG with one of two different methods of myocardial protection. The patients were randomised to receive either cold blood (COLD group) or warm modified Calafiore cardioplegia (WARM group). Microdialysis probes were implanted into the myocardium of left ventricular apical region of the heart. Cardioplegia was given antegrade only. Microdialysis measurements were performed at time intervals before, during and 24 h after cardiopulmonary bypass and analysed for glucose, lactate, pyruvate and glycerol. RESULTS: Myocardial lactate concentrations were significantly higher in the WARM group compared with that of the COLD group, while serum lactate was comparable. Glycerol was significantly higher at the end of the clamping time in the WARM group. At the same time the glucose-lactate ratio as a marker of nutritional disorder had significantly lower levels in the WARM group. The cumulative CK-MB release over 24 h was significantly higher in those hearts protected with warm blood. CONCLUSIONS: The oxidative stress measured was significantly higher in patients undergoing CABG using modified Calafiore cardioplegia, whereas the cold cardioplegia minimised the effects of aortic clamping. The results indicate that cold cardioplegia offers superior protection of the heart, in terms of more rapid normalisation of myocardial metabolism. In elective myocardial revascularisation, intermittent antegrade warm blood cardioplegia is a comparable safe method of myocardial protection. However, in patients referring to a long clamping time, advantages of cold cardioplegia for myocardial revascularisation may be magnified.

New trends in prosthesis infection in cardiovascular surgery.

BACKGROUND: Adult cardiovascular surgery entails, in many cases, the use of some kind of prosthesis. Among the potential complications, prosthetic device infection is one of the most devastating in incidence, as well as in prognosis and damage to surrounding tissues. RESULTS: The most common bacterial agents in vascular and cardiac prosthetic device infections are Staphylococcus aureus and S. epidermidis among gram-positive bacteria and Escherichia coli, Proteus mirabilis, and Pseudomonas aeruginosa among gram-negative bacteria. CONCLUSION: The alternative modalities of treatment for prosthetic device infection encompass partial or total explantation of the prosthesis and its replacement with an infection-resistant graft (e.g., homologous tissue, autologous tissue, or synthetic prosthesis bonded with antibiotics).

Microdialysis for myocardial metabolic surveillance: developing a clinical technique.

Metabolic surveillance of the myocardium is of great interest in cardiac surgery. Microdialysis allows sampling of chemical substances from the interstitial fluid for immediate analysis. The two objectives of this study were to develop a technique for simple and safe implantation of a commercially available microdialysis probe (CMA-70) into the myocardium and to obtain reference data for further use and metabolic control. Eighteen pigs were used in an experimental ischaemic heart model where the left anterior descending coronary artery was occluded for 20 min. Microdialysis was performed proximally as well as distally to the arterial occlusion site corresponding to a control and an ischaemic area in the heart. Two techniques were tried for probe implantation, using either a pacemaker wire attached to the probe tip or a needle introducer. Metabolic substrates (glucose, lactate, glycerol and pyruvate) were collected before, during and after ischaemia, for up to 6 h. Both techniques were highly effective in registering metabolic changes due to ischaemia with sharp time resolution, but the needle introducer was superior regarding probe durability. It is concluded that the CMA-70 microdialysis probe implanted with the needle introducer allows for an accurate monitoring of myocardial metabolism during a prolonged period of time. Future studies in the human heart are warranted to further validate the technique.

Coronary artery aneurysm: management and association with abdominal aortic aneurysm.

BACKGROUND: Coronary artery aneurysm (CAA) is a dilatation that exceeds 1.5 times the diameter of a normal adjacent coronary artery. Several studies suggest that pathogenetic mechanisms involved in this disease and in abdominal aortic aneurysm (AAA) are similar. Surgery for CAA is mandatory when the aneurysm is three to four times larger than the original vessel diameter. We reviewed our experience in the surgical treatment of this unusual disease and analyzed its association with AAA. MATERIALS AND METHODS: Between October 1993 and March 2005, 11 patients (9 men; mean age=66 years) underwent surgery for CAA. In all cases, coronary aneurysms were diagnosed as incidental findings in coronary angiographies. The coronary aneurysms were isolated and longitudinally incised: the proximal and distal openings were identified and sutured. The sacs were obliterated with running sutures. Myocardial protection was achieved by retrograde cardioplegia only. Coronary artery bypass grafting was performed distally to the excluded aneurysms in all patients. RESULTS: One patient died of respiratory failure early after the operations; all other patients are alive, asymptomatic for angina, and free from repeated acute myocardial infarction after a median follow-up of 76 months (range=4-141 months). A total of six patients underwent surgical repair or endoprosthesis implantation because of AAAs. CONCLUSIONS: Our operative techniques ensured durable results. We recommend screening for abdominal aneurysms in all affected patients because of the frequent association between CAA and AAA as a result of their similar pathogenetic mechanism.

The extracellular matrix of the human aortic wall: ultrastructural observations by FEG-SEM and by tapping-mode AFM.

Fragments of human ascending aorta harvested during heart surgery were cryofractured and observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Elastic fibers appear as irregular, undulated laminae of variable size and shape. Their surface shows an evident fibrous texture suggestive of a criss-crossed, delicate filamentous scaffold and is marked by a number of features such as ridges, holes and protruding ribs. At higher magnification, both SEM and AFM show the surface composed of a finely granular material, with a bead size of approximately 20 nm. However, the thickness of the metal coating in one case, and the tip convolution effect on the other, may equally result in an artifactual enlargement of the structures, so that the beads may be significantly smaller. The surfaces created by the fracture always appear smooth and compact and with this technique do not reveal significant detail. The collagen component is mostly represented by small, uniform fibrils gathered in flexuous bundles and following a wavy course not unlike that of the elastic laminae. An orthogonal lattice of small proteoglycans is readily evident even without a specific treatment. Occasionally, the fibrils appear encrusted or engulfed in a grainy matrix reminiscent of the elastic fiber surface. Fluid Tapping-Mode Atomic Force Microscopy simultaneously reveals the surface-bound proteoglycans and the inner architecture of the fibrils, composed of smaller subunits following a spiral course with a winding angle of approximately 17 degrees.

Surgical repair of post-infarction ventricular septal defect: 19 years of experience.

OBJECTIVES: To review our experience of surgical repair of post-infarction ventricular septal defect (VSD). METHODS: In the period 1983-2002, 50 patients underwent repair of VSD. Mean age was 66 years, male sex 52%. Infarct location was anterior in 60% and posterior in 40% of cases. Median interval between rupture and surgery was 2 days. Preoperative intra-aortic balloon counterpulsation was employed in 56%; a coronary angiogram was performed in 98% of cases. A patch repair technique was used in 90% of cases. Coronary bypass grafting was associated in 50% of patients. RESULTS: Mean aortic clamp time was 101+/-31 min. Global operative mortality was 36%, respectively 26.7% in anterior and 50% in posterior location (p=ns). Emergency operation and interval from rupture to surgery less than 3 days were univariate predictor of early mortality. Five years survival excluding operative deaths was 76%. CONCLUSIONS: The surgical repair of post-infarction VSD entails a high operative mortality; different techniques were employed with similar results. Emergency operation is associated with a worse short-term prognosis; long-term survival is acceptable.

["Hybrid" management of aortic coarctation associated with atrioventricular valve regurgitation in the adult]. / Trattamento "ibrido" della coartazione aortica associata a valvulopatia atrioventricolare nell'adulto.

The incidence of heart valve disease associated with aortic coarctation is 40% in patients < 30 years and 27% in younger patients. This report describes the case of a 41-year-old man, admitted for severe mitral and tricuspid valve incompetence, causing impairment of left ventricular function and pulmonary hypertension. During hospitalization an occasional finding of aortic coarctation was diagnosed. The optimal management of aortic coarctation associated with atrioventricular valve regurgitation remains a matter of debate. In this report the proper decision-making and the management are discussed.

Comparison of three strategies for myocardial protection during coronary artery bypass graft surgery based on markers of cardiac damage.

OBJECTIVES: To evaluate myocardial damage during coronary artery bypass grafting using three different intermittent cardioplegia and then measuring cTnI and CKMBm release. DESIGN AND METHODS: Forty-two patients belonging to the hypothermic crystalloid (n = 16), hypothermic (n = 13), and normothermic blood (n = 13) groups were collected when removing the aortic cross-clamp (t = 0) and after 4, 12, 24 and 48 h. For each patient, cumulative cTnI and CKMBm release was calculated as the five measurement mean. There were no significant preoperative and operative differences in the three groups. RESULTS: In the normothermic group, cTnI mean values at 4, 12, and 24 h were significantly lower than those in both hypothermic groups; moreover, CKMBm mean values were higher at 4, 12, and 24 h in the hypothermic crystalloid group and at 4 and 12 h in the hypothermic blood group than in the normothermic group. In the normothermic group, the area under the curve of the release of both markers was significantly lower than in the hypothermic groups. No significant difference was reported in the release of both markers in hypothermic groups. CONCLUSIONS: A strategy of normothermic cardioplegia seems to preserve myocardium better than hypothermic cardioplegia.