Impact of Water- and Lipid-Soluble Statins on Nonculprit Lesions in Patients with Acute Coronary Syndrome.

Statins can be differentiated into two types, based on their solubility, which have potentially differing effects on the coronary artery wall. However, suspected differences in statins' effects on plaque composition have not been systemically investigated.Sixty-seven patients with acute coronary syndrome (ACS) were randomly assigned to either atorvastatin (10 mg/day) or rosuvastatin (2.5 mg/day). Intravascular ultrasound (IVUS) and integrated backscatter (IB)-IVUS, an established tool to quantify each plaque's components, were performed immediately after emergent percutaneous coronary intervention (PCI). Follow-up IVUS was performed between 6 and 12 months after PCI. Serial changes in serum lipid profiles and plaque composition volumes were compared between the two groups.Thirty-five patients were eligible for serial IB-IVUS analyses. The mean low-density lipoprotein-cholesterol level significantly decreased in the atorvastatin and rosuvastatin groups (P < 0.001); plaque volumes were also significantly reduced from 82.0 ± 46.2 to 74.9 ± 41.3 mm3 (P = 0.01) and from 74.7 ± 35.3 to 67.7 ± 27.0 mm3 (P = 0.02), respectively. IB-IVUS revealed a significant reduction in fibrous volume from 33.8 ± 20.0 to 27.5 ± 14.9 mm3 (P < 0.01) and from 29.6 ± 13.6 to 24.8 ± 7.6 mm3 (P < 0.05), respectively; however, significant changes were not noted in the volume of the lipid pool for the atorvastatin group and the rosuvastatin group, respectively.Water- and lipid-soluble statins may be similarly effective in reducing coronary plaques in patients with ACS as judged qualitatively and quantitatively. Further study is needed to determine whether differences between water- and lipid-soluble statins affect plaque components.

Kounis syndrome caused by protamine shock after coronary intervention: A case report.

We report a case of Kounis syndrome that led to shock after protamine administration during percutaneous coronary intervention (PCI). A man in his 50s was admitted to the nearest hospital following the onset of acute myocardial infarction. Coronary angiography showed a single-vessel lesion in the left anterior descending artery (LAD). He was admitted for PCI. After heparin administration, the procedure was completed by implantation of a coronary stent with the usual procedure. For hemostasis, following protamine administration, the patient went into shock. Subsequently, electrocardiography showed bradycardia with ST-segment elevation at leads II, III, aVF, and V3-6. Cardiopulmonary resuscitation was started immediately. As pulseless electrical activity continued, extracorporeal membrane oxygenation (ECMO) was introduced. Coronary angiography demonstrated coronary spasm in the LAD. He was withdrawn from the ECMO on day 7. His intradermal tests were positive for protamine in the convalescent phase. The patient was diagnosed with protamine shock and type I Kounis syndrome. Protamine shock is not uncommon, but Kounis syndrome may be hidden in it. Thus, similar cases should not be treated as a simple protamine shock. .

Morphological and quantitative analysis of vascular wall and neointimal hyperplasia after coronary stenting: comparison of bare-metal and sirolimus-eluting stents using optical coherence tomography.

BACKGROUND: It has been suggested that sirolimus-eluting stents (SES) provoke a more sustained inflammatory response (IR) in neointimal hyperplasia (NIH). The purpose of this study was to compare morphological vessel characteristics, including post-stent IR in NIH, between patients with SES and bare metal stents (BMS) using optical coherence tomography (OCT). METHODS AND RESULTS: Thirty-seven patients underwent OCT at their post-stent follow-up. OCT signal-intensity deviation (normalized standard-deviation; OCT-NSD) values in NIH were compared between the 2 groups. In addition, the serum concentration of high-sensitivity C-reactive protein (hs-CRP) was measured. Stent-malapposition rate (1.78% vs. 0.7%; P = 0.016), uncovered stent-strut rate (16% vs. 3.7%; P = 0.0002), peri-stent ulcer like appearance (PSUA; 50% vs. 0%; P = 0.006) were all significantly higher in the SES group than in the BMS group, respectively. The OCT-NSD value was also significantly higher in the SES group than in the BMS group (0.213 ± 0.005 vs. 0.198 ± 0.005; P < 0.001), as was the hs-CRP level (2.54 ± 1.89 vs. 0.64 ± 0.3 mg/L; P = 0.0006). In addition, a significant positive correlation was found between hs-CRP and OCT-NSD (r = 0.471; P = 0.0025). CONCLUSIONS: PSUA-morphology was specific in the SES group, and higher levels of OCT-NSD and hs-CRP after SES implantation suggest sustained IR in NIH compared with following BMS implantation. These different characteristics may be some of the background that promotes thrombus formation as a late-stage post-stent complication of SES.

Low-density lipoprotein-cholesterol/high-density lipoprotein-cholesterol ratio predicts lipid-rich coronary plaque in patients with coronary artery disease--integrated-backscatter intravascular ultrasound study.

BACKGROUND: The relationship between blood lipid profile and coronary plaque tissue characteristics, and differences in the tissue characteristics between acute coronary syndrome (ACS) and chronic coronary artery disease (CCAD) are unclear. The purpose of the present study was to compare the plaque tissue characteristics in patients with ACS and CCAD and to examine the relationship between the tissue characteristics and blood lipid profile. METHODS AND RESULTS: Integrated backscatter intravascular ultrasound (IVUS) and conventional IVUS were performed in patients with ACS (n=24) and CCAD (n=68) at the time of coronary intervention. Percent tissue volume and cross-section area of lipid pool, fibrous tissue, dense fibrous and calcification were defined in target lesions. The lipid pool area (LPA) in the ACS patients was significantly higher than in the CCAD patients (LPA, 7.0+/-3.4 vs 5.1+/-3.2 mm(2), P=0.01). In the CCAD group, LPA/non-LPA ratio tended to be higher in the ACS than in the CCAD patients (1.4+/-0.9 vs 1.1+/-0.8; P=0.08), and LDL/HDL ratio was an independent predictor for LPA/non-LPA ratio (P=0.002). In addition, LDL/HDL ratio was a useful index for the prediction of a high LPA/non-LPA ratio (area under the receiver operating characteristic curve = 0.79). CONCLUSIONS: Elevated LDL/HDL ratio may be a positive predictor for coronary lipid-rich plaque and plaque vulnerability in patients with CCAD.

Comparison of long-term prognostic evaluation between pre-intervention thrombolysis and primary coronary intervention: a prospective randomized trial: five-year results of the IMPORTANT study.

BACKGROUND: Acute efficacy and long-term prognostic differences between ST-elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention (primary PCI) and those treated with pre-intervention thrombolysis combined with back-up of facilitated PCI has not been evaluated in Japanese patients. The purpose of the present study was therefore to evaluate the differences between treatment with primary PCI (primary-PCI group) and pre-treatment with tissue-type plasminogen activator (t-PA) combined with back-up of facilitated PCI (prior-t-PA group). METHODS AND RESULTS: One hundred and one patients with STEMI were randomly assigned to 2 groups. Patients in the prior-t-PA group were then divided into 2 further groups, the facilitated-PCI and prior-t-PA alone groups. The patency rate at initial angiography, left ventricular ejection fraction (LVEF) at 6 months, and the major adverse cardiac event (MACE)-free rate at 5 years were then compared between the groups. The patency rate and LVEF in the prior-t-PA group was significantly higher than in the primary-PCI group (69% vs 17% respectively, P<0.001; 61.6+/-9.5% vs 55.0+/-11.6%, respectively; P=0.01). The MACE-free rate in the prior-t-PA group, however, was lower than in the primary-PCI group (58.7% vs 80.9%; P=0.03). The MACE-free rate in the facilitated-PCI group was equal to that in the primary-PCI group (73.7% vs 80.9%; P=0.39), whereas the MACE-free rate in the prior-t-PA-alone group was significantly lower than in the primary-PCI group (48.1% vs 80.9%; P=0.01). CONCLUSIONS: Primary PCI is superior to pre-intervention thrombolysis for long-term prognosis. Moreover, facilitated PCI may be as effective as primary PCI in patients with STEMI.

Serial endovascular assessment of polytetrafluoroethylene-covered stent: Capabilities and limitations of intravascular imaging modalities affected by a temporal factor.

A 47-year-old male who previously underwent coronary bypass graft surgery was transferred to our hospital for treatment of bare metal in-stent restenosis (ISR) of severely calcified left main (LM) coronary lesion. During a repeat coronary intervention, LM coronary perforation occurred after rotational atherectomy followed by balloon dilatation. Hemostasis was successfully achieved by implantation of a single polytetrafluoroethylene (PTFE)-covered stent. Although intravascular ultrasound (IVUS) and optical coherence tomography (OCT) were documented, any additional information was not obtained except stent expansion. Routine 6-month follow-up angiography revealed no findings of restenosis. Three representative imaging modalities, IVUS, OCT, and angioscopy were applied to visualize and differentiate any structures within the PTFE-covered stent. Intravascular findings included, (1) vascular structures outside the covered stent could be observed sufficiently by both IVUS and OCT at this time that could not be seen at all just after implantation, (2) neointimal hyperplasia distributed dominantly at both stent edges, and (3) in-stent micro thrombi still existed even 6 months after implantation. Intravascular findings of PTFE-covered stent may vary between the observational periods. Furthermore, vascular healing process of this special stent may be different from those of non-covered mesh stents. .

Peripheral vasodilatory dysfunction in adult patients with congenital heart disease and severely elevated pulmonary vascular resistance.

Several studies have demonstrated that pulmonary vascular abnormalities precede alterations in aortic circulation downstream in animal models of heart failure. The relationship between increased pulmonary vascular resistance (PVR) and agonist-induced limb vasodilatory response remains unknown in patients with congenital cardiovascular shunt lesions (CSL). The authors hypothesized that patients with CSL and severely elevated PVR will show a defective vasomotor response in the peripheral vascular bed. To examine this hypothesis we measured forearm blood flow (FBF) responses to the endothelium-dependent vasodilator acetylcholine and the endothelium-independent vasodilator sodium nitroprusside. The values for these FBF responses were compared with PVR in adult patients with CSL (n=20) and healthy age- and sex-matched controls (n = 15). When patients with CSL were divided into 2 subgroups by median value of PVR, in the lower PVR subgroup, acetylcholine-induced FBF changes were selectively and significantly lower than in the healthy control group (p <0.05). In the higher PVR subgroup, FBF responses to both acetylcholine and sodium nitroprusside were significantly blunted compared to healthy controls (both p < 0.01). In addition, when FBF changes above baseline for each dose of acetylcholine and sodium nitroprusside were cumulated and used as acetylcholine response and sodium nitroprusside response, the sensitivity and specificity for identifying patients with Eisenmenger's type of CSL was 100% and 80% by acetylcholine response, and 67% and 80% by sodium nitroprusside response, respectively. In conclusion, adult CSL patients with elevated PVR and severe pulmonary arterial hypertension showed generalized vasodilator dysfunction in the forearm vasculature. This result suggests that upper limb resistance vessel dysfunction may be an indicator for advanced stage of adult patients with CSL.

Chronic thrombus occlusion after bare metal stenting in a patient with acute coronary syndrome visualized by optical coherence tomography.

We present a case of chronic thrombus occlusion visualized by optical coherence tomography (OCT) in a patient following bare metal stent (BMS) implantation. A 74-year-old Japanese man was treated with single BMS implantation for acute coronary syndrome. The second follow-up angiography demonstrated no restenosis at the BMS site in the convalescent phase before discharge. A third coronary angiography at 6 months after BMS implantation showed sub-total occlusion at a site just proximal to the BMS. OCT was performed to evaluate in-stent restenosis. OCT demonstrated an organized thrombus-like image containing a micro-channel in the target lesion. Repeat percutaneous coronary intervention (PCI) was performed with a distal protection device and we were able to aspirate some tissue from the culprit lesion. Pathological examination of this tissue revealed an organized fibrin thrombus with angiogenesis. Phosphotungstic acid hematoxylin staining and CD68 immunological staining were positive in this tissue. Moreover, immunological staining for CD34 was positive in the micro-channel of this tissue, suggesting chronic build up. This case demonstrated that chronic, organized thrombus formation is a possible cause of restenosis after BMS implantation in the convalescent phase, and that OCT is a useful modality to discriminate thrombus formation from regular neo-intimal hyperplasia in in-stent restenosis lesions.

Late stent thrombosis after discontinuation of dual anti-platelet therapy in off-label use of paclitaxel-eluting stent visualized by optical coherence tomography-3-vessel OCT study.

We observed late stent thrombosis image by optical coherence tomography (OCT) in vessels with off-label paclitaxel-eluting stents (PES) implantation. A 59-year-old Japanese man was treated with a single on-label PES for chronic coronary artery disease in the left circumflex artery. After 9 months, he was implanted with two linked PESs in the left anterior descending artery (LAD) and a single PES in the right coronary artery (RCA). He was examined for suspicion of a colon tumor by fiberscope after discontinuation of dual anti-platelet therapy without consultation. He complained of chest pain and was transferred to our center. Emergency coronary angiography demonstrated thrombotic total occlusion of the proximal LAD in the two linked PESs. After thrombus aspiration therapy, OCT was performed to evaluate the stents in the 3 vessels. The off-label two linked PESs demonstrated the same average neo-intimal hyperplasia (NIH) thickness and percentage of uncovered stent struts compared with the on-label PES in the RCA by visualized OCT image. However, the heterogeneity of NIH in the LAD stent was significantly higher than the stents in the other two vessels. The implantation of the two linked off-label and the heterogeneity of NIH may increase hyperplatelet coagulability more than on-label single PES use.