Right ventricular and septal function in patients with pulmonary hypertension.

OBJECTIVE: Pulmonary hypertension (PHT) exacerbates the functions of both ventricles. This prospective, randomised study was planned to investigate the effects of PHT on kinetics of both ventricles and the septum. METHODS: Twenty-five patients were randomly selected among the patients who had been planned to undergo mitral valve replacement (MVR) because of isolated mitral stenosis and divided into two groups according to their preoperative pulmonary artery pressure (PAP) values. Blood pool gated single photon emission tomography (BPGS) and transthoracic echocardiography were performed. Ventricles' regional, global and functional parameters were also assessed by using pulsed wave Doppler tissue imaging (DTI). RESULTS: Preoperative and postoperative PAP of the group 1 (PAP < 50 mmHg) were 40.0 ± 2.8 and 30.0 ± 2.6 mmHg (p = 0.03), group 2 (PAP ≥ 50 mmHg) were 71.9 ± 4.7 and 50.6 ± 3.5 mmHg (p < 0.05). The global right and left ventricle scores were decreased after the operation. The decrement was only significant in group 2. Considering the septal kinetics, right ventricle septal score was decreased from 7.6 to 3.3 (p < 0.05) in group 1, from 3.8 to 1.6 (p < 0.05) in group 2 postoperatively. CONCLUSION: Following MVR, a decrement in PAP values, and an improvement in ventricular function, especially in the right ventricular and septal kinetics were achieved. Furthermore, it was found that both DTI and BPGS techniques are beneficial to investigate the functional changes postoperatively and in the follow-up period of the patients who undergo mitral valve surgery.

Histological comparison of healing following tooth extraction with ridge preservation using enamel matrix derivatives versus Bio-Oss Collagen: a pilot study.

The goal of the present clinical study was to evaluate new bone formation in human extraction sockets augmented with enamel matrix derivatives (EMD) and Bio-Oss Collagen. Patients with symmetrical single-rooted teeth in the bilateral quadrants of the upper jaw condemned for extraction participated in this study. Following extraction, the sockets (20 sockets) were randomly augmented using either EMD or Bio-Oss Collagen. After 3 months of healing, bone biopsies were obtained and prepared for histological analyses. Dental implants were then placed. Implant stability quotient (ISQ) readings were obtained for each implant at the time of surgery and at 1 and 3 months postoperatively. The mean new bone formation was 34.57 ± 25.67% in the EMD sites and 28.80 ± 16.14% in the Bio-Oss Collagen sites. There was no significant difference between the groups. The ISQ values were significantly higher for the implants placed in the EMD sites at the first and third months, but no significant differences were observed in the ISQ values for the implants placed in the Bio-Oss Collagen sites. The augmentation of the extraction sockets with EMD or Bio-Oss Collagen leads to similar behaviour in bone regeneration.

EMD or subepithelial connective tissue graft for the treatment of single gingival recessions: a pilot study.

BACKGROUND AND OBJECTIVE: The combination of EMD with root-coverage procedures has been shown to promote periodontal regeneration on the exposed root surface. The aim of this randomized clinical study was to compare the efficacy of EMD with connective tissue graft (CTG) for the treatment of Miller Class I and Class II single recessions in a split-mouth design. MATERIAL AND METHODS: The study included 12 systemically healthy patients, each with two single bilateral gingival recession defects (24 recessions). One recession defect in each patient was treated with the coronally advanced flap (CAF) + EMD procedure and the other recession defect was treated with the CTG + EMD procedure, in a split-mouth study design. The parameters recession depth (RD), recession width, percentage of root coverage, height of keratinized tissue (HKT), gingival thickness, probing depth and clinical attachment level (CAL) were recorded at baseline. All parameters, except for gingival thickness, were remeasured at 6 and 12 mo. RESULTS: The mean percentage root coverage at the final evaluation was 92 ± 14% for the CAF + EMD group and 89 ± 14% for the CAF + CTG group. Both treatments resulted in statistically significant (p < 0.05) decreases in RD and recession width, and increases in HKT, at 6 and 12 mo. There was also a significant decrease in the probing depth and a significant gain in the CAL for both groups. The probing depth was statistically higher in the CAF + CTG group than in the CAF + EMD group at 6 mo (p < 0.05), while the CAL was statistically lower in the CAF + EMD group than in the CAF + CTG group at 6 and 12 mo (p < 0.05). CONCLUSION: The present study demonstrated that both CAF + EMD and CAF + CTG procedures were similarly successful in treating Miller Class I and Class II single gingival recession defects.

Posttransplantation therapeutic rapamycin concentration protects nitric oxide-related vascular endothelial function: comparative effects in rat thoracic aorta and coronary endothelial cell culture.

OBJECTIVE: To investigate the potential effects of therapeutic dosages of the immunosuppression agent rapamycin on endothelial function with regard to nitric oxide (NO) synthesis in rat thoracic aorta in vivo and rat coronary endothelial cells in vitro. MATERIALS AND METHODS: Male Wistar rats were injected with rapamycin, 1.5 mg/kg/d intraperitoneally for 14 days. After the rats were sacrificed, the thoracic aortas were suspended in organ chambers and evaluated for endothelium-dependent and endothelium-independent vascular responses. RESULTS: Rapamycin administration resulted in increased relaxant responses to L-arginine and to greater concentrations of the calcium ionophore (A23187) in the aortas. However, potassium chloride, acetylcholine, sodium nitroprusside, and N(G)-nitro-L-arginine methyl ester responses remained unchanged. In addition, phenylephrine-induced contractions were significantly decreased in the aortas regardless of the presence of functional endothelium. In a series of in vitro experiments, isolated rat coronary endothelial cells were incubated with therapeutic concentrations of rapamycin (10 nmol/L). Nitrite accumulation in the supernatants revealed that rapamycin decreased nitrite release induced by interleukin-1beta but did not affect basal or A23187-stimulated nitrite levels. Western blot analysis demonstrated that rapamycin decreased inducible NO synthase protein expression in coronary endothelial cells. CONCLUSION: Posttransplantation therapeutic concentrations of rapamycin not only preserve vascular endothelial function mediated by NO synthesis but possibly interact in vivo with adrenergic receptors in favor of vasodilatory mechanisms.

Mitral valve replacement with beating heart technique via right thoracotomy in a patient with previous Bentall operation.

Traditionally, reoperations for mitral valve replacement are carried out under cardioplegic arrest with cross-clamping of the ascending aorta via a median sternotomy. In this case, the mitral valve replacement operation was performed with an on-pump beating heart technique without cross-clamping the aorta and via a right thoracotomy because of diffuse adhesions around the ascending aortic tube graft. A 44-year-old male patient had undergone a Bentall operation via a median sternotomy for annulo-aortic ectasia 3 years ago. He was admitted to the hospital complaining of palpitation and dyspnea. Transthoracic echocardiography revealed 4th degree mitral insufficiency. Mitral valve replacement was carried out through a right thoracotomy using an on-pump beating heart technique without cross clamping the aorta. In conclusion, mitral valve replacement with an on-pump beating heart technique via a right thoracotomy offers a safe approach when excessive dissection is required to place a cross-clamp to the ascending aorta.

Immediate provisional restoration fabrication for immediate implant loading using a modified technique: a clinical report.

This article describes the immediate fabrication and placement of a provisional restoration, using a modified method for impressionmaking. An impression was made before surgery and provisional acrylic temporary restorations with composite resin frameworks were prepared on the solid-screw implant abutments. This article demonstrates this simple method and discusses the benefits of immediate provisionalization after surgery.

Collaborative therapy with nebivalol and L-NAME for spinal cord ischemia/reperfusion injury.

Postoperative neurologic deficit is the most devastating complication after thoracoabdominal aortic aneurysm repair. Our aim was to investigate whether nebivolol has protective effects during ischemia or reperfusion and the most effective mechanism of protection via inhibiting nitric oxide (NO) release with an NO synthase inhibitor in an experimental model of spinal cord ischemia/reperfusion injury. Spinal cord ischemia was induced by occlusion of the infrarenal aorta for 30 min. Thirty-one rabbits were divided into five groups according to the administration period of nebivolol and/or N(G)-nitro-L-arginine methyl ester (L-NAME): control group; group NI, nebivolol during ischemic period; group NR, nebivolol during reperfusion period; group NILR, nebivolol during ischemic period and L-NAME during reperfusion period; and group LINR, L-NAME during ischemic period and nebivolol during reperfusion period. Blood samples were taken at both ischemia and reperfusion periods to obtain nitrite/nitrate levels. After neurologic evaluation at 24 hr of reperfusion, malondialdehyde (MDA) levels were measured. Neurologic impairment was significantly lower in group LINR (Tarlov score 3.4 +/- 0.6, p < 0.05). MDA levels were lower in nebivolol-treated animals, but the lowest value was achieved in the NR group, 35.6 +/- 2.7 nmol/g (p < 0.001). Nitrite levels were decreased significantly in all nebivolol-treated animals in the reperfusion period, but the lowest value was measured in the LINR group (455 +/- 137 vs. 1,760 +/- 522 nmol/mL, p < 0.001). Prophylactic use of nebivolol reduced neurologic injury, and combining with L-NAME provided the best clinical improvement by attenuating the inflammatory mileu in this experimental model. Combination of nebivolol and L-NAME appears to be an effective option for spinal cord protection against ischemia/reperfusion injury.

Levosimendan for ischemic preconditioning in thoracic aortic aneurysm repair.

BACKGROUND AND AIM: Postoperative neurologic deficit is the most devastating complication after surgical thoracic aorta repair. Cerebrospinal fluid drainage and some medications are used for spinal cord protection during and after the operation. METHODS: A 25-year-old patient applied to our clinic with a traumatic descending aortic aneurysm. We performed a surgical repair for the aneurysm but could not achieve to place a lumbar catheter to provide cerebrospinal fluid drainage. Levosimendan was chosen for spinal cord ischemic preconditioning because of its vasodilatory effects. RESULTS: Postoperative course was uneventful. Hemodynamic and neurologic complication was not observed, and the patient was discharged from the hospital in the postoperative 5th day. CONCLUSIONS: Levosimendan can be used for preconditioning and spinal cord protection from ischemic injury during descending aorta repair. We clearly benefit from the vasodilator peculiarity of the drug for improving spinal cord perfusion.

On-pump beating heart versus hypothermic arrested heart valve replacement surgery.

BACKGROUND: Comparison of neurological parameters in patients undergoing prosthetic heart valve replacement with two operating techniques-either cardioplegic arrest of the heart under hypothermic cardiopulmonary bypass (CPB) or the heart beating on normothermic bypass, with or without cross-clamping the aorta, without cardioplegic arrest. methods: Fifty valvular surgery patients were randomly assigned into three groups. Sixteen patients underwent beating heart valve replacement with normothermic bypass without cross-clamping the aorta, 17 patients underwent the same procedure with cross-clamping the aorta and retrograde coronary sinus perfusion, and the remaining 17 patients had conventional surgery with hypothermic bypass and cardioplegic arrest. RESULTS: Two-channel electroencephalography (EEG) was recorded to assess changes in cerebral cortical synaptic activity and 95% spectral edge frequency values were recorded continuously. Bispectral monitoring was used to measure the depth of anesthesia. Blood flow rates in middle cerebral artery (MCA) were measured by transcranial Doppler (TCD). Reduction in spectral edge frequency (>50%) or bispectral index (BIS) (<20) or transcranial Doppler flow velocity (>50%) was detected in four patients in Group 1, five patients in Group 2, and three patients in Group 3. BIS or EEG values never reached zero, which indicates isoelectric silence during surgery. Gross neurological examinations were normal in all patients postoperatively. CONCLUSION: There is no difference regarding neurological monitoring results between on-pump beating heart and hypothermic arrested heart valve replacement surgery. Also no significant difference was encountered among the groups regarding the clinical outcomes.

Mitral valve replacement with the beating heart technique in a patient with previous bypass graft from ascending to descending aorta due to aortic coarctation.

BACKGROUND AND AIM: Conventional mitral valve replacement (MVR) is carried out under cardioplegic arrest with cross-clamping of the ascending aorta during cardiopulmonary bypass. In this case, MVR was performed with on-pump beating heart technique without cross-clamping the aorta because of the diffuse adhesion around the ascending aorta, and tube graft presence between ascending and descending aortas. METHODS: A 47-year-old female patient had aorto-aortic bypass graft from ascending aorta to descending aorta with median sternotomy and left thoracotomy in single stage because of aortic coarctation 2 years ago in our cardiac center. She was admitted to the hospital with palpitation and dyspnea on mild exertion. Transthoracic echocardiography revealed 4th degree mitral insufficiency. RESULTS: MVR was carried out through remedian sternotomy with on-pump beating heart technique without cross-clamping the aorta. CONCLUSIONS: MVR with on-pump beating heart technique offers a safe approach when excessive dissection is required to place cross-clamp on the ascending aorta.

A new technique for the old arterial graft: internal thoracic artery.

The internal thoracic artery (ITA) is the gold-standard conduit for coronary artery bypass surgery. It stays patent well in the long-term period, and this evidence is directly related to the superior later outcome in terms of longevity. Coronary artery bypass grafting with multiarterial grafts can be performed safely, and better long-term result can be expected with the use of arterial conduits, especially ITA. We describe a simple and practical technique for the left ITA grafting by dividing the ITA graft and using its proximal and distal parts in situ for the distal left anterior descending (LAD) artery and the obtuse marginal artery grafting.

Levosimendan effect on spinal cord ischemia-reperfusion injury following aortic clamping.

BACKGROUND AND AIM OF THE STUDY: The new calcium sensitizer, levosimendan, not only acts as a positive inotropic agent but also, vasodilates both venules and arterioles. The aim of this experimental study was to investigate whether levosimendan has protective effects on spinal cord ischemia-reperfusion injury. MATERIAL AND METHODS: Twelve New Zealand rabbits were enrolled in this study. In addition to the control group, levosimendan is administered to the experimental group with a loading dose of 12 microg/kg prior to ischemia over a 10-minute period, followed by an infusion of 0.2 microg/kg/min during the ischemia period (30-minutes). Following the neurologic evaluation at the 24th hour of reperfusion, lumbar spinal cords were removed in order to perform microscopic examination and malondialdehyde (MDA) and myeloperoxidase (MPO) measurements. RESULTS: The mean Tarlov score of the levosimendan group (3.25) was higher than the control group (0.7) (p< 0.05). MDA level was found significantly lower in the levosimendan group when compared with the control group as 1.6 +/- 0.4 nmol/gr and 189.3 +/- 43.6 nmol/gr respectively (p < 0.05). MPO level was also found statistically significant when we compared levosimendan group with the control group. It was calculated as 11.3 +/- 1.0 micro/gr tissue and 39.1 +/- 16.9 micro/gr in the levosimendan and the control groups (p< 0.05). Light microscopic examination was carried out with tissue samples in the 24th hour of the reperfusion. Levosimendan group had better preservation with the microscopic appearance with respect to the control group. CONCLUSION: Levosimendan exhibits an important protection by means of neurological outcome, histopathological, and biochemical analysis for the ischemia-reperfusion injury of the spinal cord following the aortic clamping.

How DMSO, a widely used solvent, affects spinal cord injury.

The aim of this experimental study was to investigate whether dimethylsulfoxide (DMSO) has protective effects on spinal cord ischemia-reperfusion (I/R) injury. New Zealand rabbits were enrolled in the study. In addition to the control group, the study group received 0.1 mL/kg DMSO prior to ischemia. Blood samples were taken to obtain nitrite-nitrate levels during the surgical procedure. After neurological evaluation at 24 hr of reperfusion, lumbar spinal cords were removed for electron microscopic evaluation and malondialdehyde and myeloperoxidase measurements. The mean Tarlov score of the DMSO group was higher than that of the control group. Electron microscopic examination was carried out with tissue samples at 24 hr of reperfusion. The DMSO group had better preservation with the electron microscopic scoring compared to the control group. Malondialdehyde and myeloperoxidase levels were decreased in the DMSO group compared to the control group. Nitrite-nitrate levels were also lower in the DMSO group compared to control at 5 and 30 min of reperfusion. This study demonstrates a considerable neuroprotective effect of DMSO on neurological, biochemical, and histopathological analyses during periods of spinal cord I/R injury in rabbits. Although there was a difference between the DMSO and control groups in all measured parameters in our study, this was not statistically significant. DMSO deserves further investigation related with spinal cord ischemia and reperfusion. We should also consider the effect of DMSO when we use it as a solvent or vehicle during experimental I/R models.

A Turkish family with Ellis-van Creveld syndrome in six siblings; linkage analysis on 4p16 region (D4S3360-D4S2366).

We present a Turkish family and their 6 children, consecutively affected by Ellis-van Creveld (EVC) Syndrome. Four of the affected children died in the postnatal period, and 2 of them had been admitted to the pediatric cardiology department for their cardiologic evaluation. Since they had the features of the EVC Syndrome, linkage analysis was performed with the polymorphic markers, D4S3360-D4S2366, selected from 4p 16 locus. There was complete segregation between the disease and marker allels and the two affected siblings were homozygote for the polymorphic markers, as expected in autosomal recessive inheritance. The diagnosis of EVC Syndrome was confirmed by this molecular analysis. Two cases with EVC were presented in this report. Case 1 had partial abnormal pulmonary venous return and pulmonary stenosis additional to ostium primum atrial septal defect and mitral cleft. Partial abnormal pulmonary venous return and pulmonary stenosis were previously not reported with EVC Syndrome. Postaxial polydactyly phenotype of the Case 2 differs from her brother's. There is bifid 5th metacarpal and unilateral (L) bifid middle and distal phalanges resembling syndactyly.

Penetrating cardiac injuries.

BACKGROUND: This study was planned to evaluate patients with penetrating cardiac injury. METHODS: Twenty-two patients had cardiac injury among twenty-five patients who had been referred to our hospital with a suspicion of this diagnosis. Data of the patients were retrospectively evaluated. RESULTS: Echocardiography could be performed in 11 patients with stable haemodynamics and pericardial effusion was established in all of them with one false positive result. The patient with false positive result had left internal thoracic artery and venous injury. Cardiac tamponade was seen in 17 (77%) patients. Injury sites were right ventricle 10 (45.5%), left ventricle 7 (31.8%), left ventricle consisting left anterior descending artery 2 (9.1%), right atrium 1 (4.5%) and pericardial injuries and hematoma 2 (9.1%). The mean physiologic index (PI) of the patients was 10.68+/-5.63, penetrating cardiac trauma index was (PCTI) 14.09+/-6.3, penetrating thoracic trauma index (PTTI) was 17+/-8.84 and organ injury scale according to the American Association for the Surgery of Trauma (AAST/OIS) was 3.86+/-1.25. Mortality rate was 27.3% with 6 out of 22 patients. PI, PCTI, PTTI and AAST/OIS scores of the non-survivors were significantly higher than those of the survivors (p<0.05). While there was no difference between survivors and non-survivors regarding the presence of tamponade and the frequency of the associated abdominal injury, left ventricular and left anterior descending artery injuries and associated lung injuries were more common in non-survivors (p<0.05). CONCLUSION: Non-survivors with penetrating cardiac injury have higher PI, PCTI, PTTI and AAST/OIS scores and they are more severely injured patients comparing to the survivors.

Redo valve surgery with on-pump beating heart technique.

AIM: Reoperations have become of increasing frequency in the last four decades. Redo surgery is more complex than primary surgery and is associated with higher mortality and morbidity. We present our immediate and mid-term results of mitral and aortic prosthetic valve replacement undertaken with beating heart technique. METHODS: The prospective study included 26 consecutive redo valve surgery patients who underwent valve re-replacement. The operation was carried out on a beating heart using normothermic bypass without cross-clamping the aorta for mitral valve surgery and retrograde coronary sinus normothermic noncardioplegic blood perfusion during cross-clamping the aorta for aortic valve procedures. RESULTS: Twenty-six patients (mean age 50+/-15 years) underwent reoperation with beating heart technique. Twenty (76.9%) mitral prosthetic replacements, 4 (15.4%) aortic prosthetic replacements, and 2 (7.7%) double valve replacements were achieved. Fourteen patients (53.8%) were operated for prosthetic valve dysfunction. Eighteen patients (69.2%) were in NYHA class III or IV preoperatively. Mean bypass time was 85+/-30 min. Mean duration of ventilation was 13.6+/-6 h, mean intensive unit stay was 2.8+/-6.4 days, and mean hospital stay was 8.3+/-7.2 days. Two (7.7%) patients required high dose inotropic support and in one patient (3.8%) intra-aortic balloon support was required. Pulmonary complication occurred in 1 patient (3.8%), low cardiac output in 1 patient (3.8%), and re-exploration for bleeding in 2 patients (7.7%). Operative mortality was not observed. CONCLUSION: Normothermic on-pump beating heart valve replacement offers a safe alternative to cardioplegic arrest in high-risk group. Complication rates are low and perioperative mortality is lower than with conventional surgery. Beating heart technique has the advantage of maintaining physiologic condition of the heart throughout the procedure.

A new technique of myocardial protection during aortic root replacement: antegrade/retrograde coronary perfusion.

Aortic root surgery has traditionally been performed with an arrested and cooled heart using cardioplegia. A new technique of myocardial protection was utilized in the treatment of ascending aortic aneurysm with severe aortic valve regurgitation requiring aortic root replacement with the Cabrol technique. Retrograde and antegrade perfusion of the heart with blood allowed the surgical operation to be performed safely while the heart was beating and eliminated the ischemic reperfusion injury which occurs during cardioplegic arrest and reinstitution of blood perfusion after removal of the aortic cross-clamping required in traditional techniques.

Coronary atherosclerosis distribution and the effect of blood glucose level on operative mortality/morbidity in diabetic patients undergoing coronary artery bypass grafting surgery: a single center experience.

OBJECTIVE: The study aim was to investigate the effect of blood glucose level on atherosclerotic lesion distribution and the contribution to the operative mortality/morbidity in diabetic patients who underwent coronary artery bypass grafting (CABG). METHODS: Between 1986-2003, a total of 2095 patients with diabetes mellitus underwent CABG. The analysis was carried out retrospectively from the clinical records. The patients were divided into four groups according to the blood glucose levels that were obtained when they first applied to hospital; Group 1 (492 patients with blood glucose < 120 mg/dl), group 2 (1112 patients with blood glucose - 120-200 mg/dl, group 3 (261 patients with blood glucose 201-250 mg/dl) and group 4 (230 patients with blood glucose > 250 mg/dl). One way ANOVA test was used for the statistical analysis of continuous variables and Chi-square test was used for analyzing the categorical variables. RESULTS: Emergent operation rate due to acute ischemia gradually increased from Group 1 to Group 4 and reached 6.6% in Group 4 (p=0.005). Operation time and the duration of cardiopulmonary bypass and cross clamp were significantly longer in patients with high blood glucose levels (p<0.05). Necessity for inotropic drug administration postoperatively (p<0.05) and mechanical support (p<0.05) were significantly higher also. The hospital mortality in group 3 was 9.6% and in group 4 was 11.3% (p=0.09). No statistically significant difference was found in terms of morbidity between the groups (p>0.05). The multi-vessel coronary artery disease was more common in groups with high blood glucose level (p<0.05). As the blood glucose level raised, patients were more frequently (p<0.05) confronted with distal left anterior descending artery, middle circumflex artery and right coronary artery lesions. CONCLUSION: Uncontrolled blood glucose level not only increased the perioperative complications but also the incidence of middle and distal coronary artery lesions. It is necessary to diagnose and aggressively treat the high blood glucose level especially before the CABG.

Beating heart mitral valve replacement with retrograde coronary sinus perfusion technique.

AIM: The aim of this study was to assess the efficacy and applicability of on-pump beating heart mitral valve replacement with Sorin Bicarbon prosthesis using retrograde coronary sinus perfusion. METHODS: The prospective study included 17 consecutive patients who underwent mitral valve replacement with Sorin Bicarbon prosthesis using retrograde coronary sinus perfusion. The operative variables and early outcome of this procedure are presented. RESULTS: Retrograde coronary sinus perfusion and venting the heart from the aorta and from the pulmonary vein provided good visualization of the operative field and performance of the operations without any difficulty. Partial oxygen pressures of coronary sinus perfusion blood and the returning blood from the coronary ostia were 299.7+/-30.7 and 37.6+/-6.2 mmHg respectively. Postoperative peak creatine kinase-MB and troponin T values were 58+/-28.5 IU/L and 1.5+/-0.4 ng/mL, respectively. No mortality or major complication was observed and all the patients were discharged from the hospital in good condition. CONCLUSIONS: On-pump beating heart mitral valve replacement with Sorin Bicarbon is a good surgical option, and it has the advantage of maintaining physiologic condition of the heart throughout the procedure.