Role of aerobic physical training on cardiac autonomic and morphophysiological dysfunction in hypertensive rats subjected to ovarian hormone deprivation

Here we investigated the effects of physical training on cardiovascular autonomic control and cardiac morphofunctional parameters in spontaneously hypertensive rats (SHRs) subjected to ovarian hormone deprivation. Forty-eight 10-week-old SHRs were divided into two groups: ovariectomized (OVX, n=24) and sham (SHAM, n=24). Half of each group (n=12) was trained by swimming for 12 weeks (OVX-T and SHAM-T). Cardiac morphology and functionality were assessed using echocardiography, and autonomic parameters were assessed using double pharmacological autonomic block, baroreflex sensitivity (BRS), and analyses of heart rate variability (HRV) and blood pressure variability (BPV). Ovariectomy did not influence the cardiac autonomic tonus balance unlike physical training, which favored greater participation of the vagal autonomic tonus. Ovariectomy and aerobic physical training did not modify HRV and BRS, unlike BPV, for which both methods reduced low-frequency oscillations, suggesting a reduction in sympathetic vascular modulation. Untrained ovariectomized animals showed a reduced relative wall thickness (RWT) and increased diastolic and systolic volumes and left ventricular diameters, resulting in increased stroke volume. Trained ovariectomized animals presented reduced posterior wall thickness and RWT as well as increased final diastolic diameter, left ventricular mass, and stroke volume. Ovarian hormone deprivation in SHRs promoted morphofunctional adaptations but did not alter the evaluation of cardiac autonomic parameters. In turn, aerobic physical training contributed to a more favorable cardiac autonomic balance to the vagal autonomic component and promoted morphological adaptations but had little effect on cardiac functionality.

Resveratrol Prevents Warm Ischemia-Reperfusion Injury in Liver Grafts From Non-Heart-Beating Donor Rats.

BACKGROUND: Successful liver transplantation from non-heart-beating donors (NHBDs) might enlarge donor source. Some studies have reported that resveratrol (RES), an activator of sirtuins, has cytoprotective effects on ischemia-reperfusion (I/R) injury. The purpose of this study was to investigate the effects of RES on warm I/R injury in rats. METHODS: Male Wister rats were divided into 5 groups: (1) the heart-beating (HB) group, whose livers were retrieved from HB donors; (2) the NHB group, whose livers were retrieved under apnea-induced NHB conditions; (3) the ethanol group, retrieved in the same manner as the NHB group with ethanol (10 µL) as a solvent; (4) the RES-1 group, retrieved in the same manner as the NHB group and pretreated with RES (0.4 mg/kg, dissolved in 10 µL ethanol); and (5) the RES-2 group, retrieved in the same manner as the NHB group and pretreated with RES (2 mg/kg, dissolved in 10 µL ethanol). The resected livers were perfused for 60 minutes with Krebs-Henseleit bicarbonate buffer after 6 hours of cold preservation, after which the perfusate and liver tissues were investigated. RESULTS: The bile production, portal vein flow volume, tumor necrosis factor-α level, and adenosine triphosphate level in the RES-2 group were significantly improved compared with in the NHB group. Histology revealed numerous well-preserved sinusoidal endothelial cells in the RES-2 group. CONCLUSIONS: RES might reduce warm I/R injury and improve the viability of liver grafts from NHBDs. We considered that this method may represent a promising approach for clinical liver transplantation from NHBDs.

Edaravone, a free radical scavenger, improves the graft viability on liver transplantation from non-heart-beating donors in pigs.

BACKGROUND: Although liver transplantation from non-heart-beating donors (NHBDs) is an effective way to overcome shortage of donors, primary graft nonfunction is often noted in these grafts. We have previously reported that edaravone, a free radical scavenger, has a cytoprotective effect on warm ischemia-reperfusion injury and improves the function of liver grafts from NHBDs in a rat model of ischemia-reperfusion. The purpose of this study was to investigate the effects of edaravone on liver transplantations from NHBDs. METHODS: Pigs were divided into three groups: (1) a heart-beating (HB) group (n = 5), in which liver grafts were retrieved from HB donors; (2) a non-heart-beating (NHB) group (n = 4), in which liver grafts were retrieved under apnea-induced NHB conditions; and (3) an edaravone-treated (ED) group (n = 5), in which liver grafts were retrieved in the same manner as the NHB group and treated with edaravone at the time of perfusion (3 mg/L in University of Wisconsin [UW] solution), cold preservation (1 mg/L in UW solution), and after surgery (1 mg/kg/d). The grafts from all groups were transplanted after 4 hours of cold preservation. RESULTS: In the ED group, the 7-day survival rate was significantly higher than that in the NHB group (80% versus 0%, P = .0042, Kaplan-Meier log-rank test). Furthermore, on histologic examination, the structure of sinusoids in the ED group was well preserved and similar to that in the HB group. CONCLUSIONS: Edaravone may improve the viability of liver grafts from NHBDs.

Risk factors for hepatic artery thrombosis after microsurgical vascular reconstruction in liver transplantation.

OBJECTIVE: In liver transplantation, microsurgical reconstruction of a hepatic artery is essential but requires challenging techniques. Especially in living-donor liver transplantation, the recipient artery is short and located deep in the abdominal cavity. Furthermore, hepatic artery thrombosis (HAT) can be a lethal complication. This study sought to uncover the risk factors for HAT after microsurgical vascular reconstruction. METHODS: From 1991 to 2011, we performed 151 microsurgical vascular reconstructions, including 3 deceased-donor liver transplantations. We retrospectively investigated the cases, performing univariate and multivariate analyses to identify independent risk factors for HAT. The patients had undergone ultrasonographic examinations for HAT over the first 14 days after transplantation. RESULTS: Upon univariate analysis, the risk factors identified to be associated with P < .20 were young age (P = .0484), low body weight (P = .0466), short height (P = .0128), high graft-to-recipient weight ratio (P = .0031), small liver graft volume (P = .0416), small amounts of gabexate mesilate infusion (P = .0516), and the conventional technique (without a back-wall support suture; P = .1326). A multiple logistic regression analysis identified low body weight to be the only independent risk factor for HAT. CONCLUSION: On the univariate analysis, we found that using the back-wall support suture technique contributed to the reduction of HAT, whereas on multivariate analysis, the only independent risk factor for HAT was low body weight.

Myocardial protection of the pressure overload hypertrophied heart in human cardiac surgery by acceleration of anaerobic glycolysis.

BACKGROUND: Because of the decreased tolerance to ischemia and increased reperfusion injury in hypertrophied myocardium, myocardial hypertrophy is a well known risk factor for cardiac surgery. We have previously demonstrated in a left ventricular hypertrophy (LVH) model that a highly buffered cardioplegic solution (HBS) that provided glucose as a substrate and promoted anaerobic glycolysis during ischemia afforded superior myocardial protection when compared to standard formulations. And we reported the superiority of this cardioplegia in human cardiac surgery. METHODS: In this study, 16 patients with aortic stenosis (AS) and LVH receiving HBS were reviewed and compared to another patient group with AS and LVH who received either cold blood cardioplegia (CBC; n=5) or glucose insulin potassium (GIK; n=6). RESULTS: Postoperative cardiac index was better in the HBS group than the other two groups with similar or lower catecholamine. CK-MB was lower in HBS group than GIK group, but this was not significant. Only one DC cardioversion was required in the HBS group, whereas 2 DC in the CBC group and total 7 DC in the GIK group. CONCLUSIONS: We found that histidine buffered cardioplegic solution provided comparable or better pump performance after surgery with relatively lower inotropic requirement, less DC cardioversion and homologous blood requirements for left ventricular hypertrophied heart associated with aortic stenosis.

Preoperative cerebrovascular screening before cardiovascular surgery in a high risk area of cerebrovascular events in Japan.

BACKGROUND: Cerebrovascular disease and cervical artery diseases are potentially treatable conditions that are associated with an increased incidence of stroke after cardiac surgery. This prospective study was designed to determine the prevalence of cerebrovascular diseases in the high risk population of cerebrovascular event including some young patients in Japan and establish the strategy for cardiac surgery of patients with cerebrovascular disease. METHODS: 100 (71 male, 29 female) of 126 consecutive patients undergoing cardiac surgery under cardiopulmonary bypass were screened for the presence of cerebrovascular disease by intra-arterial angiogram. RESULTS: In seven patients angiographic evaluation disclosed some evidence of cerebrovascular disease for 50% or greater stenosis or cerebral aneurysm. Preoperative 99mTc-Hexamethyl propylene amino oxime (99mTc-HMPAO) single emission computed tomography (SPECT) with combination of balloon arterial occlusion test provided detailed information of cerebral ischemic tolerance and reliable decision making for surgical repair of cerebrovascular disease. No deaths were recorded and a small stroke in one patient. CONCLUSIONS: We concluded that cerebrovascular screening in patients with cardiovascular disease may be requested in a high risk population of cerebrovascular events.

Superior myocardial protection with a new histidine-buffered crystalloid cardioplegic solution in clinical trial.

BACKGROUND: Blood cardioplegia has been widely accepted in clinical cardiac surgery based on its excellent oxygen delivery and pH buffering capacity. To further conserve blood during clinical cardiac surgery, we formulated a new crystalloid cardioplegic solution containing histidine (100 mol/L) as the pH buffering agent. METHODS: Sixty patients being applied Histidine Buffered Solution (HBS) (n = 27) or Cold Blood Cardioplegic solution (CBC) (n = 33), both at 4 degrees C, were studied prospectively. Pre- and post-bypass left-ventricular (LV) volume was measured by echocardiography. With a ventricular pressure catheter, LV pressure-volume loops were constructed to determine the slope of the end-systolic pressure-volume relationship (Emax) without inotropes. RESULTS: There were no postoperative deaths in either group. Thirty minutes after reperfusion Emax was significantly better in the HBS group than in the CBC group (6.0 +/- 1.0 mmHg/cm3 vs 3.7 +/- 0.8 mmHg/cm3). Cardiac Index was also significantly higher in HBS group than in CBC group with lower inotropic requirement. Homologous blood transfusion was avoided in 64% of the patients receiving HBS versus 48% of the patients with CBC. CONCLUSIONS: We conclude that the new histidine-buffered cardioplegic solution provides effective protection with excellent recovery of pump performance in clinical open heart surgery.

[Histidine buffered cardioplegic solution (HBS) provides effective myocardial preservation with wider safety margin in patients with prolonged ischemia].

Increasingly complex techniques of cardiac surgery often require prolonged myocardial ischemia. We previously reported a better myocardial preservation with histidine containing cardioplegia (HBS) in human open heart surgery. To see a safety margin of this cardioplegia for prolonged myocardial preservation, this study was retrospectively done. One hundred twenty-six patients received either intermittent multidose (20-30 minute) cold blood cardioplegia (CBC) plus topical cooling (aotric cross clamp time (ACC) < 120 minutes, n = 63) or HBS (n = 63). HBS group was divided into two groups with either short ACC (< or = 120 minutes, HBS-S, n = 46) or long ACC (> 120 minutes, HBS-L, n = 17). Cardiac index (C.I.) and dopamin/dobutamine requirement were measured 3, 6, and 12 hours post-bypass. Incidence of homologous blood transfusion was also studied. There was two deaths due to LOS in HBS-S group; four patients in HBS group required 5 DC cardioversion, whereas six patients required a total of 12 DC cardioversion in CBC group. Functional recovery were significantly better with significantly lower inotropic requirements in HBS-S group than CBC group and HBS-L group. Although preoperative ejection fraction and C.I. were significantly lower in HBS-L group, post-operative cardiac function and inotropic requirements in HBS-L was comparable to that seen in CBC group. We conclude that the highly buffered histidine crystalloid cardioplegia solution provides effective myocardial preservation with a wider safety margin for prolonged myocardial preservation in open heart surgery.

Regional cerebral blood flow evaluated by 99mTc-HMPAO-SPECT in patients with axillo-axillary bypass for subclavian steal syndrome.

BACKGROUND: Clear evidence of cerebral blood circulation has not been shown after axillo-axillary bypass surgery in patients with subclavian steal syndrome. METHODS: We investigated the cerebral circulation and blood flow in 3 patients receiving axillo-axillary bypass by RI angiography using 99mTc-dl hexamethyl propylene amine oxime (99mTc-HMPAO). Two patients had vertebral basilar cerebral symptoms which were related to decreased cerebral blood flow evidenced by 99mTc-HMPAO. RESULTS: After the correction, cerebral symptoms disappeared and improved cerebral blood circulation detected by 99mTc-HMPAO-SPECT. CONCLUSIONS: We concluded that axillo-axillary bypass was a fairly effective procedure to improve cerebral blood circulation evidenced by 99mTc-HMPAO-SPECT.

[A clinical application of histidine buffered cardioplegia].

Blood cardioplegia has been widely accepted due to better oxygen delivery, pH buffering and free radical scavenge. We have found that a crystalloid cardioplegia solution formulated to accelerate anaerobic glycolysis with high buffering capacity. To conserve blood cardioplegia, we formulated a crystalloid cardiopletia containing 100 mM histidine for buffering. This cardioplegia (HBS) was compared to cold blood cardioplegia in patients requiring open heart surgery. Eighty patients including HBS (n = 28), and CBC (n = 40) were involved in this study. Left ventricular end-systolic elastance (Emax; mmHg/cm3) was evaluated pre- and postoperatively. Cardiac index and inotropic requirement were also monitored at 1, 3, and 12 hours after cardiopulmonary bypass. There was no death in either group. All hearts returned to previous rhythm in HBS group, whereas total 12 DC cardioversions were requested in 6 patients. Emax was significantly higher in HBS group (5.2 +/- 0.6 mmHg/cm3) than in CBC group (3.4 +/- 0.4 mmHg/cm3). Cardiac index was also significantly higher in HBS group postoperatively than in CBC group with lower inotropic requirements. We conclude that histidine containing crystalloid cardioplegia provides excellent recovery of cardiac performance with lower inotropic requirements in open heart surgery. The ease of use, and lack of blood are other important advantages of this crystalloid cardioplegia.

Purulently infected abdominal aortic aneurysm: in situ reconstruction with transmesocolic omental transposition technique.

A new omental transposition technique was applied to a patient who underwent resection and in situ reconstruction of purulently infected abdominal aortic aneurysm to prevent recurrent retroperitoneal and graft infection. After wide separation from the transverse colon, the omental pedicle was transposed to the infrarenal retroperitoneal space through an opening of the transverse mesocolon to wrap the prosthetic graft and fill the infected space. The postoperative course was uneventful without any sign of recurrent infection in follow-up lasting 8 months. The authors' experience suggest that this 'transmesocolic' technique is an effective modality for critically ill patients with infected abdominal aorta.

[Heart failure due to severe myocardial calcification--a rare complication after irradiation on the chest wall].

A 28-year-old female who had had irradiation on the chest wall at the age of 5 as a remedy for keroid granulation after burn, recently developed congestive heart failure. Severe tricuspid regurgitation was demonstrated by echocardiography with a certain calcification in the cardiac shadow on chest radiogram. Calcified right ventricule and ventricular septum were noticed operatively, which disturbed ventricular motion and also caused tricuspid valve deformity. These calcified myocardium apparently corresponded with the irradiation field. After tricuspid valve replacement, she regained physical activity satisfactorily without congestive heart failure. Because she had no other known causes of cardiac calcification such as hypercalcemia, myocarditits, myocardial infarction or renal diseases, irradiation on the chest wall could be responsible for the severe myocardial calcification.

[A case report of combined aortic and mitral regurgitation associated with ankylosing spondylitis].

We reported a case of ankylosing spondylitis which successfully underwent aortic valve replacement for combined aortic and mitral regurgitation. A 42-year-old man was admitted with symptoms of shortness of breath and anginal pain. He was previously diagnosed ankylosing spondylitis by an orthopedician A grade III/VI to and fro murmur was audible at the left sternal border. Retrograde aortography revealed severe aortic regurgitation and mild mitral regurgitation. Cardiac catheterization showed moderately pulmonary hypertension and high pulmonary artery wedge pressure. He underwent aortic valve replacement with SJM prosthetic valve. His postoperative course was uneventful. In Japan, ankylosing spondylitis is rare disease, and cardiac lesions associated with these conditions is seldom met to us. The surgical problems and management of these lesions are discussed.

[A case of chondrosarcoma originating from the left third rib].

Chondrosarcoma of rib origin is rare in Japan. A 51-year-old man came to our hospital with chest pain and coin lesion in the left superior part of the chest X-ray film. It was suspected to be the posterior mediastinal tumor based on CT and MRI. Operation was done to remove the tumor and the histological diagnosis was chondrosarcoma. The tumor measured 2.5 x 2.6 x 2.2 cm arising from the posterior portion of the left third rib. Combined resection of descending aortic adventitia was done. The patient is doing well without symptoms of recurrence 15 months after operation.

Apico-aortic conduit bypass operation in a patient with calcified ascending aorta due to Werner's syndrome.

A 53-year-old Japanese man with Werner's syndrome underwent successful apico-aortic conduit bypass operation. Preoperative examination showed severe calcification in the aortic root and ascending aorta. A composite graft was implanted from the left ventricular apex to the descending thoracic aorta with femoro-femoral bypass. To our knowledge, this case is the first surgical correction of a cardiac lesion in a patient with Werner's syndrome.