Effect of Low-Intensity Cavitation on the Isolated Human Thoracic Artery In Vitro.

Reported here are the results of an experimental study on the response to low-intensity cavitation induced by low-frequency (4-6 W/cm2, 20 kHz and 32.6 kHz) ultrasound of isolated human arterial samples taken during conventional myocardial revascularization operations. Studies have found that low-frequency ultrasound results in a significant (48%-54%) increase in isometric contraction force and does not depend on the number of exposures (10 or 20) or the time passed since the start of ultrasound (0, 10 and 20 min), but does depend on the frequency and location (internal or external) of the blood vessels for the application of ultrasound. Diltiazem (an inhibitor of slow calcium channels) and carbachol (an agonist of muscarinic receptors) used in a concentration-dependent manner did not modify the relaxation dynamics of smooth muscle affected by ultrasound. Thus, ultrasound conditioned to the augmentation of the isometric contraction force the smooth muscle of blood vessels and did not improve endothelial- and calcium channel blocker-dependent relaxation.

[Surgical treatment of acute type A aortic dissection]. / Uminio A tipo aortos atsisluoksniavimo gydymas.

UNLABELLED: The objective of this study was to evaluate the short-term results of surgical treatment in patients with acute aortic dissection. PATIENTS AND METHODS: A retrospective analysis of 38 patients with acute type A aortic dissection who were surgically treated at the Clinic of Cardiac, Thoracic, and Vascular Surgery, Hospital of Kaunas University of Medicine, from January 2004 to December 2007 was conducted. The diagnosis of aortic dissection was confirmed by employing special techniques. Two-dimensional transthoracic echocardiography was performed in 34 (89.5%) patients; transesophageal echocardiography, in 24 (63.1%); computed tomography, in 29 (76.3%); coronagraphy and angiography, in 20 (52.6%). Preoperative shock was reported in 3 (7.9%) and cardiac tamponade in 18 (47.4%) cases. More than half (57.9%) of patients were operated on within the first 24 hours after admission. In the majority of cases (73.7%), the diameter of the aorta exceeded 4 cm. In the presence of type A aortic dissection, all patients underwent surgery on cardiopulmonary bypass; its duration varied from 20 to 485 min, with a mean of 214.6+/-102.9 min. The mean aortic cross-clamp time was 114.5+/-62.7 min. Complete circulatory arrest was needed in the majority of cases (86.8%), and it lasted 2 to 97 min (mean, 27.4+/-18.6 min). During cardiopulmonary bypass, body temperature was decreased to 17-28 degrees C (mean, 18.9+/-1.95 degrees C). The duration of surgery ranged from 1 to 14 hours, with a mean of 6.1+/-2.49 hours. During the early postoperative period, 12 (31.6%) patients died. Postoperative bleeding was seen in 16 (42.1%) patients, and 6 of them died later. Due to prolonged bleeding, 4 (10.5%) patients were left with an open sternum after surgery. Resternotomy was performed in 9 patients; 3 of them died due to multiorgan injury. During postoperative period, cardiogenic shock of various degrees was seen in 7 (18.4%) patients. Central nervous system injury occurred in 9 (23.7%) patients. CONCLUSION: The main risk factor for acute aortic dissection is the diameter of the aorta exceeding 4 cm (diagnosed in 73.7% of cases). The main postoperative complications are bleeding (42.1%), injuries of central nervous system (23.7%), and cardiogenic shock (18.4%).

Matrix metalloproteinase-3 gene polymorphism and dilatative pathology of ascending thoracic aorta.

Matrix metalloproteinase-3 (MMP-3) degrades extracellular matrix and may lead to development of dilatative pathology of ascending thoracic aorta. Expression of MMP-3 depends upon the 5A/6A polymorphism in the promoter region. An increased number of 5A alleles leads to high expression of MMP-3. Thus, objective of the study was to determine whether the 5A/6A polymorphism in the promoter region of MMP-3 gene is associated with the development of dilatative pathology of ascending thoracic aorta. We studied 76 patients (age ranged from 31 to 81 years; median age, 64 years) who underwent aortic reconstruction surgery due to dilatative pathology of ascending thoracic aorta and a random sample of the population (n=604) aged 25-64 years, all from Lithuania. DNA was analyzed by using real-time polymerase chain reaction to genotype polymorphism 5A/6A at a position -1171 of the MMP3 gene promoter. The prevalence of MMP-3 genotypes was similar in the group of dilatative pathology of ascending thoracic aorta and random sample of population. The frequency of 5A allele did not differ significantly between both groups and was 0.506 and 0.514, respectively. Male carriers of 5A/5A genotype were significantly younger compared with those with the 6A/6A genotype. In conclusion, the frequency of MMP-3 promoter 5A/6A genotypes did not differ between the group of patients with dilatative pathology of ascending thoracic aorta and the random sample of population, but the males with dilatative pathology of ascending thoracic aorta and 5A/5A genotype required aortic reconstruction surgery at the younger age than the males carrying 6A/6A genotype in the MMP-3 promoter region.

[Late results of minimally invasive operations of myocardial revascularization in patients with acute coronary syndrome]. / Minimalios apimties miokardo revaskulizacijos be dirbtines kraujo apytakos, atliktos uminiu iseminiu sindromu laikotarpiu, itaka velesnems iseminems pasekmems.

UNLABELLED: The aim of the study was to compare late results of the minimally invasive operations of myocardial revascularization and conservative treatment in patients with acute ischemic syndrome. MATERIAL AND METHODS: Demographic, clinical and echocardiographic data was collected on patients with acute ischemic syndrome; data of 109 patients treated conservatively and data of 26 patients, who underwent minimal invasive operation of myocardial revascularization during acute phase of ischemic syndrome, were compared and ischemic consequences after one-year follow up period were determined in both groups. RESULTS: The patients of both groups did not differ significantly according to the most clinical characteristics. One third of the patients in the surgery group had previous myocardial infarction, also they had higher rate of paroxysmal atrial fibrillation (26.9% vs 6.4%) and acute left ventricular failure (73.1% vs 44.0%) than the patients without operation. During one-year follow up period there were no cases of lethal events or myocardial infarction in the surgical group, however 37.5% of them had mild angina pectoris. At that time lethal outcome was observed in 6.1%, myocardial infarction in 3.5% and mild-severe angina pectoris in 68.8% of patients. CONCLUSION: The functional status of the patients significantly improved during one-year period after minimally invasive operation of myocardial revascularization compared to the patients treated conservatively.

["Off-pump" myocardial revascularization: experience in the Clinic of Cardiosurgery, Kaunas University of Medicine]. / Beapytakines vainikiniu kraujagysliu operacijos (Kauno medicinos universiteto kliniku Kardiochirurgijos klinikos patirtis).

UNLABELLED: According to indications there is no difference in results of grafts patency and left ventricle function after minimal invasive myocardial revascularization in comparison to typical operation with cardiopulmonary bypass and cardioplegia. Only ranges of troponin T (TnT), CK and CK-MB are statistically significantly lower in the group of operations without cardiopulmonary bypass and cardioplegia. MATERIAL AND METHODS: According to possibilities different surgical technic of minimally invasive myocardial revascularization was used in 119 patients with chronic ischemic heart disease. Dynamic perioperative level of cardiospecific agents (TnT, CK, CK-MB) was determined in 30 cases; left ventricle function was echoscopically analyzed (ejection fraction, left ventricle wall motion index, left ventricle end diastolic diameter) for 70 patients and postoperative angiographic control was done for 46 patients. RESULTS: All operations were done in the Clinic of Cardiosurgery of Kaunas University of Medicine until July 1, 2003. An analysis of operative data of 119 cases with ischemic heart disease is presented. All patients underwent thoracic coronary and aortocoronary bypass grafting using minimal invasive cardiosurgical technique on the beating heart without cardiopulmonary bypass ("off-pump"). In most cases median sternotomy was used. Left internal thoracic artery or saphenous vein were applied as a grafts. Perioperative investigation of TnT, CK and CK-MB for 30 patients in early postoperative period showed low level of signs of myocardial injury. Postoperative angiographic control of grafts in 46 patients was done until 30(th) postoperative day and showed excellent patency rate of arterial and vein bypasses. In cases of complete revascularization marked and statistically significant improvement of the left ventricle function was found. CONCLUSIONS: According to indications minimally invasive ("off-pump") operation is alternative method to traditional myocardial revascularization with cardiopulmonary bypass and cardioplegia. In these cases lower level of perioperative myocardial injury is observed; improvement of left ventricle function and high postoperative graft patency are similar to those after traditional operations.

[Anesthesia used in minimally invasive myocardial revascularization surgery]. / Anestezija, naudojama minimalios apimties miokardo revaskulizacijos operacijai.

As myocardial revascularisation operations without cardiopulmonary bypass are getting more popular, more facts are found about their surgical techniques. However, the questions considering their anesthesia, the protection of myocardium and other are not widely analyzed. The specific features of anesthesia in cardiosurgery, such as methods of ventilation, combination of induction and general anesthesia with epidural anesthesia, usage of cardiac protection and ischemic preconditioning, monitoring, heparin management, usage of drugs, postoperative pain management are given in this article. As anesthesiological and surgical techniques are getting better and the professional skills of surgeons and anesthesiologists are improving, given data should improve the perspectives of minimally invasive cardio surgery operations and anesthesia in Lithuania.

[Contraversions of simultaneous coronary artery bypass grafting, abdominal aorta and major vascular operations]. / Kompleksiniu sirdies, aortos ir stambiuju kraujagysliu operaciju kontraversijos.

OBJECTIVE: Patients with coronary artery disease associated with peripheral vascular disease often raise problems of operative strategy. Particularly the sequence of procedures in which lesions must be treated is a frequent source of controversy. The aim of this study was to research surgical strategy, early and late clinical outcomes for patients undergoing one-stage coronary and abdominal aortic or magistral artery surgical interventions. MATERIAL AND METHODS: From 1999 through 2002 twenty eight patients underwent combined major vascular reconstruction with coronary artery bypass grafting. RESULTS: In group with abdominal aortic aneurysm 2 patients died. One patient died from intraoperative acute abdominal aortic aneurysm and bifemoral artery thrombosis with continuous bleeding from the vascular prosthesis in association with disseminated intravascular coagulation. Another patient died from bleeding from the sudden multiple gastroduodenal ulcers on post-operative day eight. In groups with peripheral vascular occlusive disease and carotid artery disease there were no deaths. CONCLUSIONS: The data show that combined coronary artery bypass grafting and vascular operations are feasible on patients with concomitant carotid artery or peripheral vascular occlusive disease. Management of CAD associated with abdominal aortic aneurysm remains controversial.

[Late results of minimally invasive operations of myocardial revascularization]. / Minimalios apimties miokardo revaskulizacijos operaciju velyvieji rezultatai.

Minimally invasive operations of myocardial revascularization (MIMR) are done using usual approaches, but without extracorporeal circulation and cardioplegia. Doing these operations according to indications, there is no difference in early results of these operations and the operations with extracorporeal circulation and extracorporeal circulation (1, 2). OBJECTIVE. To evaluate the late results of minimal invasive operations of myocardial revascularization 1 year after intervention, according to detection of patient's functional class, findings of echocardiography and stress test. Also to compare the results of operations in patient's groups of age up to 65 years old and over 65 years old. MATERIAL AND METHODS. From 88 patients, that underwent minimal invasive operations of myocardial revascularization, 34 patients were checked according to investigation protocol, evaluating functional class, myocardial contractility and stress test tolerance. The late results of two different groups of age were compared (each group includes 17 cases). RESULTS. All patients have survived 1 year after operation. Findings of stress test showed, that 60% of patients have reached 100 W and more strain tolerance. Pectoral angina was detected in 12% of cases. There was no difference, that was improved statistically in findings of myocardial contractility before and after operation. CONCLUSIONS. Evaluating the late results of minimally invasive operations of myocardial revascularization (1 year after operation), we can consider, that these operations, that were done according to indications, are improved, safe and suitable also to elderly patients.

[The first clinical experience and technical peculiarities of mitral valve homograft implantation]. / Pirmoji klinikine patirtis ir techniniai ypatumai implantuojant mitralinio voztuvo homografta.

INTRODUCTION: Surgical interventions because of mitral valve disease have been ascribed since 1951. Many changes within mitral valve replacement have passed including closed and open mitral commissurotomy, mitral valve repair operations implantation of mechanical, biological heart valve and finally use of mitral valve homograft. Despite changes in chirurgical tactics and medico-technical environment, mitral valve homograft implantation remains one of the most complex surgical interventions. Surgical and technical details of mitral valve homograft implantation are discussed. OBJECTIVE: to estimate technical difficulties and anatomical positioning of mitral valve homograft considering a spectrum of indications of mitral valve replacement. CASE REPORT: 62-year-old woman 26 years ago underwent mitral valve replacement with Starr-Edwards mitral valve prosthesis, because of rheumatic heart disease by homograft. Due to malfunction of the mitral valve prosthesis, and progressive left ventricular failure patient was reoperated on 26(th) of February 2002. Fresh antibiotic preserved mitral valve homograft was implanted. Surgical techniques were guided using left ventricle size measurement indicated by echocardiography. RESULTS: The technique described by Acar/Carpentier was used except of mitral valve annuloplasty ring implantation. Peri- and early postoperative period was free of homograft related complications. The left ventricle function was improving and the heart size decreased dramatically during first postoperative week. CONCLUSION: The most important peculiarities for mitral valve homograft implantation are echocardiography data and intraoperative left ventricle measurements. Homograft implantation techniques are rather demanding therefore indications for mitral valve replacement have to be selected carefully and should be based on the presence of severe mitral valve dysfunction in order to achieve best hemodynamic results and prevent patient from anticoagulation therapy.