[Graft Kink with Hemolytic Anemia Caused by Enlargement of the Residual False Lumen in the Aortic Root:Report of a Case].

A 67-year-old male underwent ascending aortic replacement for Stanford type A acute aortic dissection four years ago. Residual false lumen in the aortic root and mild to moderate aortic regurgitation were noted postoperatively. Two and a half years later, he presented with hemolytic anemia and shortness of breath. Computed tomography (CT) revealed aneurysmal aortic root and severely kinked vascular prosthesis, and echocardiography showed severe aortic regurgitation. It was considered that the proximal residual false lumen gradually enlarged, and the graft was pushed up distally and kinked, resulting in hemolytic anemia. Surgical treatment was indicated because of deteriorating shortness of breath due to hemolytic anemia (Hb 6.7 g/dl, LDH 1,528 U/l) and aortic regurgitation. Aortic root replacement was successfully performed and hemolytic anemia improved immediately after surgery.

Hemoptysis.

Hemoptysis is a rare complication of acute aortic dissection. A 77-year-old woman was admitted to our department with epigastralgia and hemoptysis. Computed tomography showed Stanford A acute aortic dissection and massive posterior mediastinal hematoma which extended along the right pulmonary artery. Hemoptysis is a lethal sign of aortic dissection, therefore, emergency ascending aortic replacement was performed with a good clinical outcome.

[Resection for the Recurrence of Hepatocellular Carcinoma in the Inferior Vena Cava and Right Atrium under Deep Hypothermic Circulatory Arrest].

A 77-year-old man underwent extended right lobectomy of the liver for rupture of hepatocellular carcinoma. Recurrence in the inferior vena cava andright atrium was noted 30 months after surgery. We performedextirpation of this tumor thrombosis under retrograde cerebral perfusion during deep hypothermic circulatory arrest. The pericardium was cut through sternotomy, and cooling was initiated. After cardiac arrest at 20.4°C, the inferior vena cava was separated. An incision was made in the right atrium andthe tumor thrombus was extirpated. In the meantime, brain protection was maintainedby retrograde cerebral perfusion. The patient was discharged on day 12 without postoperative complications. He remains alive 6 months after surgery without recurrence. This procedure prevented pulmonary embolism due to tumor thrombosis release. It was also possible to perform the procedure with retrograde cerebral perfusion.

Momentary and wide aortic regurgitation as an indicator of aortic dissection.

A 55-year-old female with a history of hypertension was admitted for dyspnea, epigastralgia and nausea. A chest X-ray showed pulmonary congestion. Transthoracic echocardiography (TTE) revealed severe left ventricular dysfunction with akinesis of the infero-posterior wall and Doppler color-flow mode showed mild aortic regurgitation (AR). Noninvasive positive pressure ventilation, intravenous heparin and diuretics were administered. Follow-up TTE revealed a dissection flap as well as momentary and wide AR only during isovolumetric relaxation. Contrast-enhanced computed tomography of the chest revealed Stanford type A aortic dissection. A momentary and wide AR in echocardiograms might serve as an important and useful indicator of aortic dissection in patients with acute myocardial infarction and congestive heart failure.

Uncertainty of axillary artery perfusion during surgery for acute aortic dissection.

We treated a patient with acute aortic dissection, which affected the innominate and carotid arteries. Although the true lumen was adequately wide and cerebral malperfusion deemed unlikely, extracorporeal circulation through the femoral artery caused right cerebral malperfusion, and addition of right axillary artery perfusion was ineffective. Several minutes after innominate artery snaring, cerebral blood flow was suddenly restored and the clinical outcome was favorable. Axillary artery perfusion is occasionally unreliable and inevitably demands careful cerebral flow monitoring. A dead-end false lumen in the innominate and carotid arteries requires special caution. A dual-artery perfusion strategy permits innominate artery occlusion as an emergency measure against unexpected malperfusion.

[Persistent cerebral malperfusion following central aortic repair for acute aortic dissection involving the right carotid artery; efficacy of direct carotid artery cannulation].

A 61-year-old man suddenly developed transient left hemiplegia and consciousness disturbance. Computed tomography showed acute Stanford type A aortic dissection. Dissection affected the entire right common carotid artery, and its false lumen extremely compressed the true lumen. The right common carotid artery, along with the right femoral and the left axillary arteries, was used as an inflow of cardiopulmonary bypass during emergency surgery. The ascending aorta that included a large intimal tear was replaced. However, systemic reperfusion either through the femoral artery or through a side branch of vascular prosthesis failed to restore the right cerebral blood flow due to persistent true lumen obstruction by the expanded false lumen in the innominate artery. Therefore, ascending aorta-right carotid artery bypass using that side branch was performed immediately. Though temporary cerebral malperfusion could cause dismal outcome, direct carotid artery cannulation played a key role in this successfully-treated patient.

Extremely localized aortic dissection and intussusception of the intimal flap into the left ventricle.

Stanford type A aortic dissection frequently deforms the aortic root and causes aortic regurgitation (AR). On the rare occasion, massive AR can occur due to circumferential intimal disruption and prolapse of the cylinder-shaped intimal flap into the left ventricle. Because of the critical, general, and hemodynamic state of such patients, surgery for this condition carries a high risk. A 62-year-old woman suffered acute chest pain and fell into cardiogenic shock. Computed tomography and transthoracic echocardiography failed to identify the etiology of this rapid hemodynamic collapse. Transesophageal echocardiography (TEE) demonstrated circumferential intimal disruption, 3 centimeters above the aortic valve annulus; a very localized aortic dissection in the proximal ascending aorta; and a to-and-fro motion of cylinder-shaped intima causing severe AR. The dissection did not affect the aorta beyond the intimal tear, and TEE was the only useful modality for the diagnosis. Emergency replacement of the ascending aorta and resuspension of the aortic valve was successfully performed. Residual AR was absent, and the postoperative course was uneventful.

[Refractory pulmonary hypertension following mitral valve repair necessitating percutaneous cardiopulmonary support].

A 37-year-old woman underwent semi-emergency mitral valve plasty for severe mitral regurgitation and congestive heart failure. Although repair was successfully performed and the left ventricular function was maintained, refractory pulmonary hypertension precluded cessation of cardiopulmonary bypass. Inhalation of nitric oxide was ineffective, and assist circulation was required. All data obtained from the Swan-Ganz catheter and other routine monitors were devastating, and the patient showed no clinical recovery in the early postoperative period. However, transesophageal echocardiography (TEE) performed on the 2nd postoperative day (POD) revealed much better filling of the left heart and the patient was weaned from assist circulation on the 4th POD. Pulmonary vascular disease was denied histologically. Late cardiac catheterization disclosed normal pulmonary artery pressure and resistance. TEE played a key role during very complicated postoperative management. Monitoring of the left atrial pressure might be necessary in cases that require assist circulation due to pulmonary vasoconstriction.

[Aortic valve replacement without blood transfusion in a patient with osteogenesis imperfecta].

Osteogenesis imperfecta (OI) is a hereditary systemic connective tissue disorder that is rarely associated with valvular heart diseases. Cardiovascular surgery for patients with OI carries high morbidity and mortality, which mostly results from bleeding tendencies caused by tissue and capillary fragility. We report a 47-year-old male with isolated aortic regurgitation, who underwent aortic valve replacement (AVR) with a mechanical prosthesis without blood transfusion. The perioperative course was uneventful. We believe that a meticulous technique and a planned strategy to avoid every damage to fragile tissues, particularly to bones, are very important during surgery for patients with OI.

Overexpression of integrin-linked kinase induces cardiac stem cell expansion.

OBJECTIVE: Recent evidence suggests that the adult heart contains stem cells that are capable of self-renewal as well as multilineage differentiation. However, their inherent capacity for self-renewal is limiting to cell replacement applications. Integrin-linked kinase is a multifunctional protein kinase that activates Wnt target genes implicated in the symmetric replication of embryonic stem cells. METHODS: Primary cultures derived from human fetal cardiac tissue (19-22 weeks' gestation) were grown in serum-free media and evaluated for the presence of cardiac progenitor cells. The effect of integrin-linked kinase was ascertained by adenoviral overexpression. RESULTS: Cultures infected with wild-type integrin-linked kinase yielded a significant (P = .001), approximately 5-fold increase in both the absolute number and the frequency of c-Kit-positive, myosin-negative cells. Cardiospheres, comprised on morphologically homogeneous, anchorage-independent cells, were reproducibly present at days 7 to 10 and formed derivative cardiospheres in multiple passages. Integrin-linked kinase infection of primary cardiac cell cultures resulted in a greater number of primary spheres at each cell density tested, compared with untreated and virus controls (P = .001). Secondary spheres transferred to differentiation medium and 5-aza-deoxycytodine (10 micromol/L) generated cells exhibiting biochemical evidence of differentiation into cardiomyocytes, smooth muscle cells, and endothelial cells. CONCLUSIONS: This study demonstrates that self-renewing cardiospheres generated from human fetal cardiac cells are composed of cells exhibiting the properties of stem cells, including the capacity for self-renewal and multilineage differentiation. Our results suggest that integrin-linked kinase promotes stem cell amplification and can be applied therapeutically to overcome a major limitation in the field of cardiac regenerative medicine.

Integrin-linked kinase expression is elevated in human cardiac hypertrophy and induces hypertrophy in transgenic mice.

BACKGROUND: Although numerous signaling pathways are known to be activated in experimental cardiac hypertrophy, the molecular basis of the hypertrophic response inherent in human heart diseases remains largely unknown. Integrin-linked kinase (ILK) is a multifunctional protein kinase that physically links beta-integrins with the actin cytoskeleton, suggesting a potential mechanoreceptor role. METHODS AND RESULTS: Here, we show a marked increase in ILK protein levels in hypertrophic ventricles of patients with congenital and acquired outflow tract obstruction. This increase in ILK was associated with activation of the Rho family guanine triphosphatases, Rac1 and Cdc42, and known hypertrophic signaling kinases, including extracellular signal-related kinases (ERK1/2) and p70 S6 kinase. Transgenic mice with cardiac-specific expression of a constitutively active ILK (ILK(S343D)) or wild-type ILK (ILK(WT)) exhibited a compensated ventricular hypertrophic phenotype and displayed an activation profile of guanine triphosphatases and downstream protein kinases concordant with that seen in human hypertrophy. In contrast, transgenic mice with cardiomyocyte-restricted expression of a kinase-inactive ILK (ILK(R211A)) were unable to mount a compensatory hypertrophic response to angiotensin II in vivo. CONCLUSIONS: Taken together, these results identify ILK-regulated signaling as a broadly adaptive hypertrophic response mechanism relevant to a wide range of clinical heart disease.

Cardioprotective stress response in the human fetal heart.

OBJECTIVE: We propose that the fetal heart is highly resilient to hypoxic stress. Our objective was to elucidate the human fetal gene expression profile in response to simulated ischemia and reperfusion to identify molecular targets that account for the innate cardioprotection exhibited by the fetal phenotype. METHODS: Primary cultures of human fetal cardiac myocytes (gestational age, 15-20 weeks) were exposed to simulated ischemia and reperfusion in vitro by using a simulated ischemic buffer under anoxic conditions. Total RNA from treated and baseline cells were isolated, reverse transcribed, and labeled with Cy3 or Cy5 and hybridized to a human cDNA microarray for expression analysis. This analysis revealed a highly significant (false discovery rate, <3%) suppression of interleukin 6 transcript levels during the reperfusion phase confirmed by means of quantitative polymerase chain reaction (0.25 +/- 0.11-fold). Interleukin 6 signaling during ischemia and reperfusion was assessed at the protein expression level by means of Western measurements of interleukin 6 receptor, the signaling subunit of the interleukin 6 receptor complex (gp130), and signal transducer of activated transcription 3. Posttranslational changes in the protein kinase B signaling pathway were determined on the basis of the phosphorylation status of protein kinase B, mitogen-activated protein kinase, and glycogen synthase kinase 3beta. The effect of suppression of a prohypertrophic kinase, integrin-linked kinase, with short-interfering RNA was determined in an ischemia and reperfusion-stressed neonatal rat cardiac myocyte model. Endogenous secretion of interleukin 6 protein in culture supernatants was measured by enzyme-linked immunosorbent assay. RESULTS: Human fetal cardiac myocytes exhibited a significantly lower rate of apoptosis induction during ischemia and reperfusion and after exposure to staurosporine and recombinant interleukin 6 compared with that observed in neonatal rat cardiac myocytes ( P < .05 for all comparisons, analysis of variance). Exposure to exogenously added recombinant interleukin 6 increased the apoptotic rate in both rat and human fetal cardiac myocytes ( P < .05). Short-interfering RNA-mediated suppression of integrin-linked kinase, a prohypertrophy upstream kinase regulating protein kinase B and glycogen synthase kinase 3beta phosphorylation, was cytoprotective against ischemia and reperfusion-induced apoptosis in neonatal rat cardiac myocytes ( P < .05). CONCLUSIONS: Human fetal cardiac myocytes exhibit a uniquely adaptive transcriptional response to ischemia and reperfusion that is associated with an apoptosis-resistant phenotype. The stress-inducible fetal cardiac myocyte gene repertoire is a useful platform for identification of targets relevant to the mitigation of cardiac ischemic injury and highlights a novel avenue involving interleukin 6 modulation for preventing the cardiac myocyte injury associated with ischemia and reperfusion.

[Pseudoaneurysm of the left ventricle following suppurative pericarditis and sepsis due to Staphylococcus aureus: a case report].

A 35-year-old diabetic man presented with a left ventricular aneurysm very close to the mitral valve annulus. He had been conservatively treated for suppurative pericarditis and sepsis due to Staphylococcus aureus during the previous 3 weeks. The left ventricular aneurysm rapidly enlarged (6 cm in diameter) and the patient underwent emergent surgery. Cardiopulmonary bypass and cardioplegic arrest were induced, and the left ventricular aneurysm orifice was closed with a double layer of autologous pericardium. Mitral valve function was not impaired. He has been doing well for 4 years. Surgery is indicated as soon as possible after the diagnosis of infective left ventricular aneurysm.

Mid-term results of aortoplasty for dilated ascending aorta associated with aortic valve disease.

BACKGROUND: Dilatation of the ascending aorta concomitant with aortic valve disease is occasionally associated with progressive enlargement of the ascending aorta or acute aortic dissection (AAD). However, surgical procedure of choice for the aorta and its indication are controversial. PATIENTS AND METHODS: From July 1995 to August 2001, 10 patients with a moderately dilated ascending aorta (mean diameter, 52+/-4.8 mm) underwent concurrent aortic valve replacement (AVR) and aortoplasty. The aortic valve was bicuspid in eight patients. To tailor the ascending aorta 30-35 mm in diameter, the aortic wall was partially resected along the aortotomy, and the aorta was directly closed. RESULTS: Operation time and most of other perioperative variables were comparable to those of patients who underwent isolated AVR. The aortic diameter was reduced to 36.1+/-4.1 mm. Nine patients survived to hospital discharge uneventfully, but one patient developed disruption of the suture line in the aorta and died. During follow-up, no patient suffered AAD but redilatation was observed in one patient. In the two problematic patients, the ascending aorta was larger than 55 mm, and its media was histologically abnormal. CONCLUSION: In patients with dilated ascending aorta less than 55 mm in diameter, aortoplasty can be a procedure of choice. However, a prosthetic graft replacement is recommended when the diameter of the ascending aorta is larger than 55 mm.