Characterization of transient atrial rhythm occurring between typical atrial flutter and its termination with class III drugs.

BACKGROUND: The transient atrial rhythm intervened between atrial flutter (AFL) and its termination during class III antiarrhythmic drug therapy for AFL has not been characterized well. METHODS: Eighteen patients with typical AFL were included in this study. The transient atrial rhythms converted from AFL with different class III antiarrhythmic drugs, ibutilide (group 1, N = 8) and nifekalant (group 2, N = 10), were determined. RESULTS: AFL terminated, without any intervened transient atrial rhythms, due to conduction block within the isthmus in three patients in each group. The transient atrial rhythm could be characterized into the following types of rhythm based on the initiating mechanisms. (1) The lower-loop reentry or atrial fibrillation that was triggered by a premature excitation in the lateral right atrium caused by breakdown of a functional barrier predisposed AFL to the termination in three patients in each group. (2) The return excitation that repetitively emerged within the isthmus collided with the antegrade excitation, resulting in the termination in two group 1 patients and in one group 2 patient. In the patients who developed these atrial rhythms, the cycle length (CL) oscillation coincidently increased with emergence of such rhythms and became significantly greater than that in the patients who did not develop such transient rhythms (P < 0.05). CONCLUSIONS: The transient atrial rhythms that emerged with class III drugs are associated with the disruption of the stable AFL reentry that may be triggered by similar electrophysiologic mechanisms with different class III drugs. The increased flutter CL oscillation developing after such drugs might signal the AFL termination.

Spontaneous isolated dissection of the superior mesenteric artery.

A case of a 63-year-old man with isolated dissection of the superior mesenteric artery (SMA), demonstrated by enhanced computed tomography (CT) and abdominal angiography, was admitted to our hospital. The severity of this disease varies from mild to severe; the severe cases require surgery. But the mild cases, like the one presented here, only need conservative therapy. This case demonstrated the usefulness of anticoagulation therapy and the indications for surgical and radiological intervention.

Preoperative administration of methylprednisolone attenuates cytokine-induced respiratory failure after esophageal resection.

Proinflammatory cytokines have been implicated in mediating respiratory failure associated with major surgery. We investigated the effect of giving glucocorticoids preoperatively for the prophylaxis of surgical stress and the association of cytokine levels, such as interleukin-6 (IL-6) and interleukin-8 (IL-8), with oxygenation after esophagectomy. We studied 17 patients who underwent subtotal esophagectomy. Seven patients (steroid group) were chosen at random to be given methylprednisolone (10 mg/kg) and 10 patients (control group) to be given saline intravenously before operation. Plasma and bronchoalveolar lavage fluid (BALF) IL-8 levels in the control group were significantly higher than those in the steroid group. In both groups, plasma IL-6 levels were significantly higher than those in BALF, but in contrast, BALF IL-8 levels were significantly higher than plasma levels of IL-8 postoperatively. The PaO(2)/FiO(2) ratio was significantly reduced in the control group. The PaO(2)/FiO(2) ratio of the control group had significantly lower values than that of the steroid group. There was significant correlation between BALF IL-8 levels and the PaO(2)/FiO(2) ratio postoperatively. We conclude that preoperative administration of methylprednisolone may attenuate postoperative reduction of arterial oxygen saturation by suppressing the release of cytokines.

Surgical thrombectomy for right heart thrombus with acute aortic dissection.

An 81-year-old female complaining of severe back pain was admitted to hospital and diagnosed with acute type A aortic dissection with a thrombosed false lumen. Aggressive antihypertensive therapy was selected. On day 8, computed tomography showed pulmonary artery thrombus, and transthoracic echocardiography showed a 76×70 mm worm-like floating right heart thrombus. Thrombolytic therapy is reported to be the optimal treatment for patients with pulmonary embolism and floating right heart thrombus, but is contraindicated in acute aortic dissection. The patient underwent surgical thrombectomy, which revealed thrombus entrapped in the Chiari network. An inferior vena cava filter was placed. The patient recovered uneventfully and was discharged home after initiation of warfarin therapy.

Treatment of visceral malperfusion in acute type B aortic dissection by percutaneous endovascular fenestration using a stent, with additional stenting of the true lumen.

Patients with acute type B aortic dissection (ABAD) are often treated medically. However, ABAD is a potentially serious emergency if complicated by acute organ ischemia. The therapeutic strategy for ABAD with visceral malperfusion remains controversial. Because emergent surgery has a high mortality rate, emergent endovascular treatment can be performed instead. We report a case of endovascular fenestration with stenting for visceral malperfusion in ABAD. One stent was inserted across the intimal flap to keep the fenestrated site open, and another stent was placed into the narrowed true lumen. This therapeutic strategy may be feasible for ABAD with acute malperfusion.

Inhibitory effect of valsartan against progression of left ventricular dysfunction after myocardial infarction: T-VENTURE study.

BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEI) reduce the mortality in the chronic phase of myocardial infarction (MI), and similar effects of angiotensin receptor blockers (ARB) have been reported. However, these effects of ARB have not yet been established in Japanese patients. A multicenter randomized study was designed for the present study to examine the effect of valsartan as compared to that of ACEI against left ventricular dysfunction after MI. METHODS AND RESULTS: Patients with acute MI were randomly allocated to either the valsartan group (n=120; mean age 63 +/-1.0) or the ACEI group (n=121; mean age 62.9 +/-1.0) and followed up until 6 months. Left ventriculography was performed during hospital admission and at 6 months. The blood pressure was similar in the 2 groups throughout the study. The incidences of cardiovascular events and target vessel revascularization were similar, although that of adverse events was significantly higher in the ACEI (12.4%) than in the valsartan group (3.3%; P<0.05). There were no differences in left ventricular ejection fraction and left ventricular end-diastolic volume index between the groups. CONCLUSIONS: Valsartan exhibits similar efficacy effective to that of ACEI in preventing left ventricular dysfunction in Japanese patients with acute MI, and is, in addition, better tolerated than ACEI.

Initial experiences of removal of intra-aortic balloon pumps with the Angio-Seal.

Angio-Seal, a vascular hemostasis device, has been shown to be safe and effective in rapidly achieving hemostasis after cardiac catheterization or coronary intervention. We propose that similar results can be obtained with Angio-Seal when removing an intra-aortic balloon pump (IABP). We studied 16 patients in whom Angio-Seal was utilized in IABP removals. The primary safety endpoint was a composite of major complications such as retroperitoneal bleeding, vessel occlusion, loss of distal pulses, vascular surgery or death, and minor complications such as hematoma (> 10 cm), AV fistula or pseudoaneurysm by 7 days after removal. The time-to-hemostasis was 2-5 minutes (mean 3.3 minutes). There were no instances of major or minor complications by the seventh day in any patients.