Impact of accelerated washout of Technetium-99m-sestamibi on exercise tolerance in patients with acute coronary syndrome: single-center experience.

Technetium-99m-sestamibi (99mTc-sestamibi) single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients with acute coronary syndrome (ACS) could be used to assess area-at-risks, as well as myocardial infarct or saved sizes. In patients with ACS, accelerated washout of 99mTc-sestamibi during early and delayed imaging in the acute phase may suggest mitochondrial dysfunction in the injured but salvaged myocardium. However, the link between 99mTc-sestamibi accelerated washout and exercise tolerance is unknown. The purpose of this study was to investigate a possible association between 99mTc-sestamibi accelerated washout and exercise tolerance in acute ACS patients as they progressed into the chronic phase. One hundred and sixty-five patients with ACS who underwent 99mTc-sestamibi SPECT MPI during the acute phase were recruited. On this basis, we calculated the total perfusion deficits (TPDs) for early (1 h after tracer injection) and delayed (4 h after tracer injection) images using automated quantification software. We then subtracted the early TPDs from the delayed TPDs to calculate the ΔTPD. We conducted a cardiopulmonary exercise test in acute and chronic phases. We divided two groups according to the median ΔTPD (the ΔTPD ≥ 4 group and the ΔTPD < 4 group) and compared anaerobic threshold (AT; ml/kg/min) between the groups. For anaerobic threshold (AT) improvement in data analysis, we employed multivariate logistic regression analysis. A total of 101 ST-segment elevation myocardial infarctions, 36 non-ST-elevation myocardial infarctions, and 28 unstable angina pectoris events were reported as ACS. From acute phase (10.8 ± 4.2 ml/kg/min) to chronic phase (11.9 ± 2.3 ml/kg/min), the AT in the ΔTPD ≥ 4 group was significantly increased (p < 0.0001). This trend was also seen in the ΔTPD < 4 group from acute (11.4 ± 1.8 ml/kg/min) to chronic phase (12.1 ± 2.2 ml/kg/min, p = 0.015). AT was lower in the ΔTPD ≥ 4 group in the acute phase (p = 0.027), but there was no difference in AT between the two groups in the chronic phase (p = 0.60). ΔTPD and the absence of diabetes were both independent predictors of AT improvement in multivariate logistic regression analysis. Receiver-operating characteristic curve analysis determined that ΔTPD = 6 was the best cut-off value, with 60.0% sensitivity and 71.4% specificity, respectively. The accelerated washout of 99mTc-sestamibi in patients with ACS during the acute phase could help to predict improvement in exercise tolerance in the chronic phase.

[Passive Orthostatism Using Tilt Table in Critical Patients after Cardiovascular Surgery].

Previously, we performed passive orthostatism using a tilt table for the purpose of early mobilization in intensive care unit patients after cardiovascular surgery. In this study, we introduced VitalGo Total Lift Bed( TLB), which does not require patient-transfer before passive orthostatism, to reduce the burden on patients and medical staff. No obvious adverse events were found throughout the study. In the TLB group, number of medical staff required to perform the passive orthostatism was significantly less compared to the conventional tilt table group.

[Passive Orthostatism Using a Tilt Table in Patients with Impaired Oxygenation after Cardiovascular Surgery].

Passive orthostatism using a tilt table was introduced in patients with impaired oxygenation [Pao2/Fio(2 P/F) ratio < 300] after cardiovascular surgery. Our passive orthostatism protocol was as follows. Patient was transferred to a tilt table under endotracheal intubation with pulmonary artery catheter monitoring, and rested for 10 minutes in a supine position, followed by 45-degree tilt for 5 minutes, and then passive orthostatism at 60-degree for 25 minutes. P/F ratio was significantly improved during passive orthostatism. Improvement in P/F ratio was confirmed even 1 hour after completion of the protocol. No obvious adverse events were found throughout the protocol. On average, 15 hours (2~72 hours, median 4 hours) after the introduction of passive orthostatism, weaning from respirator was achieved.

[Thoracentesis under Standing with Assistance of a Tilt Table in Critical Patients after Cardiovascular Surgery].

For safe and effective drainage in patients with pleural effusion after cardiac surgery, ultrasound-guided thoracocentesis was carried out under standing with assistance of a tilt table. Thoracocentesis was performed in 5( 11%) of the 44 patients who were treated under passive orthostatism using a tilt table. Four cases were under intubated-ventilator assist, and 2 cases were under intraaortic balloon pumping( IABP). No adverse events occurred. Thoracocentesis under standing with assistance of a tilt table can be safely performed.

Long-term changes in neointimal hyperplasia following implantation of bare metal stents assessed by integrated backscatter intravascular ultrasound.

In-stent restenosis (ISR) is a common phenomenon with bare metal stents (BMSs) in the early stage after implantation. However, ISR occurs at a lower rate with long time after BMS implantation. We assessed changes over time in neointimal hyperplasia following BMS implantation using integrated backscatter intravascular ultrasound (IB-IUVS). Thirty-six patients who received target lesion revascularization (TLR) to treat ISR were classified according to the duration of the interval between stent implantation and TLR: the early group (within first year n = 25) and the VL group (very late ISR ≥5 years, n = 11). IB-IUVS was used to evaluate within-stent sites from the proximal to the distal edge of the stent. IB-IVUS color maps were then constructed by tracing the stent struts and vessel lumen. Neointimal tissue was classified as high-IB (IB <-29 dB; a representative cord of calcification), middle-IB (-49 dB ≤ IB < -29 dB; fibrosis), or low-IB (-49 dB ≤ IB; lipid pool). We compared percent (%) volume, average %area of cross-sectional area (CSA), and %area of minimum CSA of each component between the groups. There were no significant differences in %volume, average %area of CSA, or %area of minimum CSA for the high-IB component between groups. The %low-IB components were 20.0 ± 8.8 % for volume, 20.1 ± 8.9 % for mean CSA, and 17.6 ± 8.5 % for minimum CSA in the early group. On the other hand, in the VL group, the %low-IB components were significantly increased to 31.8 ± 7.9 % for volume (p < 0.01 vs. the early group), 31.2 ± 7.6 % for mean CSA (p < 0.01 vs. the early group), and 33.1 ± 12.3 % for minimum CSA (p < 0.01 vs. the early group). By contrast, the %middle-IB component showed a reduction in extended time, with %volume of the middle-IB decreasing from 78.3 ± 8.1 to 66.4 ± 7.1 %, average mean %area of CSA from 78.2 ± 8.2 to 66.9 ± 6.9 %, and % area of minimum CSA from 80.7 ± 7.9 to 65.5 ± 11.4 % (p < 0.01;. the early vs. the VL group). Our results suggest that in-stent neointimal tissues developing over time consist of an increased low-IB component and a decreased middle-IB component and may contribute an increased of lipidemic component and a decreased of fibrotic component.

Outcomes of patients with stable low-risk coronary artery disease receiving medical- and PCI-preceding therapies in Japan: J-SAP study 1-1.

BACKGROUND: Stable coronary artery disease (CAD) is classified into 2 types: high-risk (ie, 3-vessel disease, left main trunk lesions, or ostial lesions of the left anterior descending (LAD)) and low-risk (1- or 2-vessel disease other than ostial lesions of the LAD), which comprise the majority of CAD patients. According to ACC/AHA/ACP-ASIM guidelines for low-risk CAD, anti-anginal agents should be initially administered to control attacks, then coronary intervention should be considered when medical therapy is not effective (medical-preceding therapy: M). In Japan, however, the initial treatment is generally percutaneous coronary intervention (PCI) combined with medical therapy (PCI-preceding therapy: P). METHODS AND RESULTS: In the present study the long-term outcomes of 190 M patients and 192 matched P patients at 34 nationwide hospitals were surveyed over 3 years (mean: 3.4 years) starting in 2000. Age, gender, initial severity of anginal symptoms, number of lesion vessels, risk factors and prescriptions were similar between the 2 groups. During the 3.4-year follow-up, additional PCI or coronary artery bypass grafting was required in 9.4% of the M group and in 33.2% of the P group. The rates of cardiac death were similar (1.6% in M and 2.6% in P). The overall rate of cardiac death and acute coronary syndrome was 2.1% in M and 4.7% in P, but the difference was not significant. The grade of anginal symptoms 12 months later was well improved in both M (1.6+/-1.4 to 0.6+/-0.9) and P (1.7+/-1.4 to 0.3+/-0.7) and there was no significant difference. Averaged annual medical cost was lower in M than in P (4.4-fold lower in the first year and 3.1-fold by the next year). CONCLUSIONS: The present study suggests that M and P for Japanese low-risk CAD may have a similar effect on long-term prognosis, but M is cheaper.

Assessment of acute myocardial infarction in Japan by the Japanese Coronary Intervention Study (JCIS) Group.

BACKGROUND: Until now, large-scale nationwide surveys of acute myocardial infarction (AMI), such as those performed in Europe and America, have not been performed in Japan. Therefore, in 2000 the Japanese Coronary Intervention Study (JCIS) group conducted a nationwide survey on the incidence of AMI in Japan. METHODS AND RESULTS: Questionnaires were collected from 8,268 facilities throughout Japan. The total annual number of patients with AMI was 66,459 (52.4 patients/10(5) population), and the AMI incidence rate in Japan was approximately 25% of that in the United States. Most facilities with AMI patients treated less than 50 AMI patients annually, and that number was 45.0% of total AMI patients. The incidence of AMI patients was highest in Kochi, Kumamoto, and Wakayama prefectures, and lowest in Yamanashi, Saitama and Shiga prefectures. The ratio of the highest incidence to the lowest incidence was 2.0. A significant correlation was observed between the mean age of the prefectural population, as a coronary risk factor, and the incidence of AMI. CONCLUSIONS: The incidence of AMI in Japan is approximately 25% that in the United States and it varies considerably among the prefectures, one of the causes being the difference in the mean age. This provides important information for assessing the guidelines for Japanese patients with AMI.