Ikuyoshi Watanabe

Cardiopulmonary cerebral resuscitation using emergency cardiopulmonary bypass, coronary reperfusion therapy and mild hypothermia in patients with cardiac arrest outside the hospital

OBJECTIVES The purpose of this study was to evaluate the efficacy of an alternative cardiopulmonary cerebral resuscitation (CPCR) using emergency cardiopulmonary bypass (CPB), coronary reperfusion therapy and mild hypothermia. BACKGROUND Good recovery of patients with out-of-hospital cardiac arrest is still inadequate. An alternative therapeutic method for patients who do not respond to conventional CPCR is required. METHODS A prospective preliminary study was performed in 50 patients with out-of-hospital cardiac arrest meeting the inclusion criteria. Patients were treated with standard CPCR and, if there was no response, by emergency CPB plus intra-aortic balloon pumping. Immediate coronary angiography for coronary reperfusion therapy was performed in patients with suspected acute coronary syndrome. Subsequently, in patients with systolic blood pressure above 90 mm Hg and Glasgow coma scale score of 3 to 5, mild hypothermia (34 C for at least two days) was induced by coil cooling. Neurologic outcome was assessed by cerebral performance categories at hospital discharge. RESULTS Thirty-six of the 50 patients were treated with emergency CPB, and 30 of 39 patients who underwent angiography suffered acute coronary artery occlusion. Return of spontaneous circulation and successful coronary reperfusion were achieved in 92% and 87%, respectively. Mild hypothermia could be induced in 23 patients, and 12 (52%) of them showed good recovery. Factors related to a good recovery were cardiac index in hypothermia and the presence of serious complications with hypothermia or CPB. CONCLUSIONS The alternative CPCR demonstrated an improvement in the incidence of good recovery. Based upon these findings, randomized studies of this hypothermia are needed.

Effect of Pravastatin on Coronary Plaque Volume

A volumetric analysis by 3-dimensional intravascular ultrasound revealed that lipid-lowering therapy with pravastatin significantly reduced coronary plaque volume. The changes in plaque volume were inversely correlated with the changes in plasma levels of high-density lipoprotein cholesterol but not with changes in levels of total cholesterol or low-density lipoprotein cholesterol.

Takotsubo-shaped cardiomyopathy with type I CD36 deficiency

A transient left ventricular apical ballooning (so-called “ampulla” or “Takotsubo-shaped” cardiomyopathy) with type I CD36 deficiency is described in a 71-year-old woman. The patient was referred because of chest pain and worsening of dyspnea. Electrocardiogram showed T-wave inversions on the precordal leads, and acute coronary syndrome was suspected. Left ventricular apical ballooning was observed by echocardiogram and left ventriculography, and coronary arteriography did not reveal any significant stenosis. Left ventricular motion normalized at the follow-up period and there were no increases in specific markers for myocardial damage, such as myocardial band fraction of creatine kinase and troponin T, through out the admission. 123I-metaiodobengylguanidine myocardial single photon emission computed tomography (SPECT) revealed decreased accumulation areas at the apex, while 201Tl SPECT showed normal accumulation. An abnormal metabolism of cardiac free fatty acid was suggested by lack of accumulation of 123I beta-methyliodophenyl pentadecanoic acid (BMIPP) SPECT. No CD36 expression in either platelets or monocytes/macrophages was shown using flow cytometer analysis and type I CD36 deficiency was diagnosed. DNA sequencing showed that the patient had compound heterozygosity of the CD36 gene (a nucleotide change in C478T and an adenine insertion at nucleotide 1159 in exon 10). Although CD36 deficiency is thought to be involved with many cardiovascular disease and metabolic abnormalities, Takotsubo-shaped cardiomyopathy with CD36 deficiency had not been reported. Further studies of Takotsubo-shaped cardiomyopathy and CD36 deficiency may reveal an association between this cardiomyopathy and specific genetic profiles.

Selective decrease in lysis of old thrombi after rapid administration of tissue-type plasminogen activator

The safety of thrombolytic therapy of acute myocardial infarction could be improved if a method were developed to dissolve fresh occlusive coronary thrombus without simultaneously dissolving hemostatic thrombi outside the coronary arteries. This study is based on the assumption that, in a patient with evolving acute myocardial infarction, hemostatic thrombi are likely to be older than the thrombus responsible for occlusion of the coronary artery. It explored whether the relative rates of lysis of fresh and old thrombi could be influenced by the rapidity of recombinant tissue-type plasminogen activator (rt-PA) administration. In each of 17 dogs, two 1 h and two 24 h old thrombi were produced by inserting copper coils into both jugular and both femoral veins. After 24 h and 1 h, respectively, the coils with the thrombi were removed, weighed and inserted into the adjacent carotid and femoral arteries. A 1 mg/kg body weight dose of rt-PA was given either over 180 or over 30 min. The coils were removed and weights of the residual thrombi determined at the end of the 180 min infusion (Group I), at the end of the 30 min infusion (Group IIA) and 45 min after the 30 min infusion (Group IIB). The 24 h old thrombi were lysed significantly less than the 1 h old thrombi in all three experimental groups: 53.9 +/- 4.8% (mean +/- SE) versus 86.1 +/- 2.5% in Group I (p less than 0.001), 16.6 +/- 3.5% versus 65.2 +/- 6.0% in Group IIA (p less than 0.001) and 21.6 +/- 5.4% versus 91.7 +/- 1.7% in Group IIB (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Reperfusion strategy for acute myocardial infarction in elderly patients aged 75 to 80 years.

The increasing elderly population will influence the treatment policies adopted in cases of acute myocardial infarction. Considering reperfusion therapy in elderly patients with acute myocardial infarction, we compared three strategies, as follows: primary percutaneous coronary intervention (primary PCI: n = 26), facilitated PCI with half the standard dose of mutant tissue-type plasminogen activator (t-PA) (half + PCI: n = 24), and facilitated PCI with a standard dose of mutant t-PA (standard + PCI: n = 15) between patients 75 and 80 years of age. The rate of acquisition of thrombolysis in myocardial infarction (TIMI-3) flow on initial coronary arteriography was significantly lower in the primary PCI group than in the other two groups (7.7% in the primary PCI group vs 60% in the half + PCI and 66.7% in the standard + PCI group). The incidence of hemorrhagic complications including blood transfusion was not significantly different between primary PCI and facilitated PCI. Considering reperfusion therapy in elderly patients with acute myocardial infarction, we concluded that facilitated PCI may be effective in elderly patients aged 75–80 years.

Efficacy of Calcium Channel Blocker in the Secondary Prevention of Myocardial Infarction

BACKGROUND Calcium channel blockers (CCBs) may have a positive influence on the long-term prognosis of Japanese patients with ischemic heart disease. METHODS AND RESULTS The effect of nifedipine-retard (NR) (n=202) compared with that of non-CCB treatment (n=92) on the secondary prevention of myocardial infarction (MI) was retrospectively investigated in patients who had survived acute MI between 1987 and 1996. The primary endpoint was the occurrence of cardiac death or non-fatal MI. The median follow-up was 6.3+/-2.4 years. The incidence of cardiac events was 8.9% in the NR group and 14.1% in the non-CCBs group (p=0.14, odds ratio (OR): 0.584, 95% confidence interval (CI): 0.286-1,193). However, subanalysis revealed that NR significantly reduced the incidence of cardiac events in patients aged less than 55 years (4.2 vs 18.2%, p=0.016, OR: 0.180, 95%CI: 0.045-0.721) and those who did not smoke (8.6 vs 16.4%, p=0.048, OR: 0.462, 95%CI: 0.203-0.999). CONCLUSION Although this was a retrospective analysis, it showed that NR did not cause an increase in the incidence of cardiac events in post-MI patients; it even prevented cardiac events, especially in those who were less than 55 years of age and in non-smokers, suggesting the potential usefulness of CCBs in the secondary prevention of MI in Japan.

Unexpected coronary vasospasm of a contralateral artery during balloon angioplasty.

It is unusual for coronary vasospasm to develop following angioplasty of a coronary vascular lesion that is located elsewhere. We experienced a rare case of shock with vasospasm of the right coronary artery in a patient following balloon angioplasty performed for stent restenosis of the left anterior descending artery.