Takeshi Shirayama

Aldosterone Directly Induces Myocyte Apoptosis Through Calcineurin-Dependent Pathways

Background—Aldosterone has recently attracted considerable attention for its involvement in the pathophysiology of heart failure, in which apoptotic cell loss plays a critical role. This study examined whether aldosterone directly induces myocyte apoptosis via its specific receptors. Methods and Results—Neonatal rat cardiac myocytes were exposed to aldosterone (10−8 to 10−5 mol/L). Nuclear staining with Hoechst 33258 showed that aldosterone induced myocyte apoptosis in a dose- and time-dependent fashion. Treatment of myocytes with 10−5 mol/L aldosterone significantly increased the percentage of apoptosis (15.5±1.4%) compared with serum-deprived control (7.3±0.6%). Radio ligand binding assay revealed the existence of plasma membrane receptor with high affinity (Kd, 0.2 nmol/L) for aldosterone in cardiac myocytes but not in fibroblasts. Aldosterone rapidly (≈30 seconds) mobilized [Ca2+]i that was blocked by neomycin. Aldosterone induced dephosphorylation of the proapoptotic protein Bad, enhancement of mitochondrial permeability transition, decrease in mitochondrial membrane potential, and release of cytochrome c from the mitochondria into the cytosol with concomitant activation of caspase-3. These effects of aldosterone were inhibited by concurrent treatment with either an L-type Ca2+ channel antagonist, nifedipine, or inhibitors for the Ca2+-dependent phosphatase calcineurin, cyclosporin A and FK506. Conclusions—The present study demonstrates for the first time that the specific plasma membrane receptor (coupled with phospholipase C) for aldosterone is present on cardiac myocytes and that aldosterone accelerates the mitochondrial apoptotic pathway through activation of calcineurin and dephosphorylation of Bad, suggesting that the proapoptotic action of aldosterone may directly contribute to the progression of heart failure.

Prognostic impact of systolic blood pressure at admission on in-hospital outcome after primary percutaneous coronary intervention for acute myocardial infarction

BACKGROUND Data regarding the relationship between systolic blood pressure (SBP) at admission and in-hospital outcome in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) are still lacking in Japan. METHODS AND RESULTS A total of 1475 primary PCI-treated AMI patients were classified into quintiles based on admission SBP (<105 mmHg, n=300; 105-125 mmHg, n=294; 126-140 mmHg, n=306; 141-158 mmHg, n=286; and ≥159 mmHg n=289). The patients with SBP<105 mmHg tended to have higher age, previous myocardial infarction, chronic kidney disease (CKD), Killip class≥3 at admission, right coronary artery, left main trunk (LMT), or multivessels as culprit lesions, larger number of diseased vessels, lower Thrombolysis In Myocardial Infarction (TIMI) grade in the infarct-related artery before primary PCI, and higher value of peak creatine phosphokinase concentration. Patients with SBP<105 mmHg had a significantly higher mortality, while mortality was not significantly different among the other quintiles: 24.3% (<105 mmHg), 4.8% (105-125 mmHg), 4.9% (126-140 mmHg), 2.8% (141-158 mmHg), and 5.2% (≥159 mmHg) (p<0.001). On multivariate analysis, Killip class≥3 at admission, LMT or multivessels as culprit lesions, admission SBP<105 mmHg, CKD, and age were the independent positive predictors of in-hospital mortality, whereas admission SBP 141-158 mmHg and TIMI 3 flow after PCI were the negative ones, but admission SBP 105-125 mmHg, admission SBP 126-140 mmHg, and admission SBP≥159 mmHg were not. CONCLUSIONS These results suggest that admission SBP 141-158 mmHg might be correlated with better in-hospital prognosis, whereas admission SBP<105 mmHg was associated with in-hospital death in Japanese AMI patients undergoing primary PCI.

Prognostic impact of pulse pressure at admission on in-hospital outcome after primary percutaneous coronary intervention for acute myocardial infarction

Data regarding relationship between pulse pressure (PP) at admission and in-hospital outcome in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) are still lacking. A total of 1413 primary PCI-treated AMI patients were classified into quintiles based on admission PP (<40, n = 280; 40–48, n = 276; 49–57, n = 288; 58–70, n = 288; and ≥71 mmHg, n = 281). The patients with PP < 40 mmHg tended to have higher prevalence of male, smoking, and Killip class ≥3 at admission; right coronary artery, left main trunk (LMT), or multivessels as culprit lesions; larger number of diseased vessels; lower Thrombolysis in Myocardial Infarction (TIMI) grade in the infarct-related artery before/after primary PCI; and higher value of peak creatine phosphokinase concentration. Patients with PP < 40 mmHg had highest mortality, while patients with PP 49–57 mmHg had the lowest: 11.8 % (<40), 7.2 % (40–48), 2.8 % (49–57), 5.9 % (58–70), and 6.0 % (≥71 mmHg). On multivariate analysis, Killip class ≥3 at admission, LMT or multivessels as culprit lesions, chronic kidney disease, and age were the independent positive predictors of the in-hospital mortality, whereas admission PP 49–57 mmHg, hypercholesterolemia, and TIMI 3 flow before/after PCI were the negative ones, but admission PP < 40 mmHg was not. These results suggest that admission PP 49–57 mmHg might be correlated with better in-hospital prognosis in Japanese AMI patients undergoing primary PCI.

Systolic blood pressure at admission, clinical manifestations, and in-hospital outcomes in patients with acute myocardial infarction

BACKGROUND Several clinical studies have demonstrated an inverse relationship between systolic blood pressure (SBP) at admission and in-hospital mortality in patients hospitalized for acute myocardial infarction (AMI). However, data on the relation between admission SBP and in-hospital prognosis in AMI patients are still lacking in Japan. METHODS AND RESULTS A total of 1211 AMI patients were classified into quintiles based on SBP at hospital admission (<106 mmHg, n = 241; 106-125 mmHg, n = 239; 126-140 mmHg, n = 244; 141-159 mmHg, n = 238; and ≥ 160 mmHg, n = 249). The patients with SBP < 106 mmHg tended to have higher age, Killip class ≥ 3 at admission, right coronary artery, left main trunk, or multivessels as culprit lesions, larger number of diseased vessels, lower Thrombolysis In Myocardial Infarction grade in the infarct-related artery before primary percutaneous coronary intervention (PCI), and higher value of peak creatine phosphokinase concentration. Patients with SBP <106 mmHg had a significantly higher mortality, while mortality was not significantly different among the other quintiles: 25.7% (<106 mmHg), 5.4% (106-125 mmHg), 5.7% (126-140 mmHg), 2.5% (141-159 mmHg), and 5.6% (≥ 160 mmHg) (p<0.001). On multivariate analysis, Killip class ≥ 3 at admission, admission SBP <106 mmHg, and age were the independent positive predictors of in-hospital mortality, whereas admission SBP 141-159 mmHg and primary PCI were the negative ones, but admission SBP 106-125 mmHg, admission SBP 126-140 mmHg, and admission SBP ≥ 160 mmHg were not. CONCLUSIONS These results suggest that admission SBP 141-159 mmHg might be correlated with better in-hospital prognosis, whereas admission SBP <106 mmHg was associated with in-hospital death in Japanese patients hospitalized for AMI.

Predictors of nonoptimal coronary flow after primary percutaneous coronary intervention with stent implantation for acute myocardial infarction.

BACKGROUND Predictors of suboptimal coronary flow in the infarct-related artery (IRA) after stent-based primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) have not been fully investigated. METHODS AND RESULTS Using the AMI-Kyoto Multi-Center Risk Study database, we retrospectively compared clinical manifestations and in-hospital prognosis between AMI patients undergoing stent-based primary PCI with final Thrombolysis In Myocardial Infarction (TIMI) grade < or = 2 in the IRA (nonoptimal group, n=69) and those with final TIMI grade 3 (optimal group, n=1200). The nonoptimal group had higher prevalence of Killip class > or = 3 at admission, higher frequency of mechanical support devices during procedures, larger value of maximal creatine phosphokinase, and a significantly higher in-hospital mortality rate (27.5% for nonoptimal vs. 9.0% for optimal, P<0.001), compared with the optimal group. On multivariate analysis, Killip class > or = 3 at admission was the independent predictor of the final nonoptimal flow (odds ratio 2.33, 95% confidence intervals 1.27-4.26 P=0.006), but TIMI 3 flow before primary PCI and elapsed time (symptom onset-to-admission time)<24h were not. CONCLUSIONS Killip class > or = 3 at admission is an independent predictor of the final nonoptimal flow in AMI patients undergoing primary PCI with stent implantation.

Relationship Between Mean Blood Pressure at Admission and In-Hospital Outcome After Primary Percutaneous Coronary Intervention for Acute Myocardial Infarction

A J-shaped or U-shaped curve phenomenon might exist between systolic blood pressure (SBP) or pulse pressure (PP) at admission and in-hospital mortality in Japanese patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI). However, data regarding a relationship between mean blood pressure (MBP) at admission and in-hospital outcome in AMI patients undergoing primary PCI are still lacking in Japan.A total of 1,413 primary PCI-treated AMI patients were classified into quintiles based on admission MBP (< 79 n = 283, 79-91 n = 285, 92-103 n = 285, 104-115 n = 279, and ≥ 116 mmHg n = 281). Patients with MBP < 79 mmHg had a significantly higher in-hospital mortality, while mortality was not significantly different among the other quintiles: 16.6% (< 79), 4.9% (79-91), 3.9% (92-103), 3.2% (104-115), and 5.0% (≥ 116 mmHg). On multivariate analysis, Killip class ≥ 3 at admission, LMT or multivessels as culprit lesions, admission MBP < 79 mmHg, and age were independent positive predictors of in-hospital mortality, whereas hypercholesterolemia and TIMI 3 flow before/after PCI were negative predictors, while the other MBP categories were not.These results suggest that admission MBP < 79 mmHg might be associated with in-hospital death, and the in-hospital prognostic effects of MBP, the steady component of blood pressure, at admission might be different from those of SBP or PP, the pulsatile component of blood pressure, at admission in Japanese AMI patients undergoing primary PCI.

Influence of previous myocardial infarction site on in-hospital outcome after primary percutaneous coronary intervention for repeat myocardial infarction

BACKGROUND Recurrent acute myocardial infarction (AMI) is a disastrous condition with high in-hospital morbidity and mortality. However, the relation between location of previous myocardial infarction (MI) and in-hospital outcome in repeat-AMI patients undergoing primary percutaneous coronary intervention (PCI) remains unclear. METHODS AND RESULTS Using the AMI-Kyoto Multi-Center Risk Study database, clinical background, angiographic findings, results of primary PCI, and in-hospital prognosis were retrospectively compared between primary PCI-treated AMI patients with previous anterior MI (anterior group, n=151) and those with previous non-anterior MI (non-anterior group, n=157). Clinical backgrounds, angiographic findings, results of primary PCI, and in-hospital outcome did not differ significantly between the two groups. On multivariate analysis, Killip class > or =3 at admission, number of diseased vessels > or =2 or diseased left main trunk at initial coronary angiography, and age were the independent predictors of in-hospital mortality in the recurrent-AMI patients, but not the anterior location of previous MI. CONCLUSIONS These results suggest that among recurrent-AMI patients undergoing primary PCI, in-hospital prognosis mostly depends on the severity of acute heart failure at the onset and the residual myocardial ischemia rather than previous MI sites.

Clinical manifestations and effects of primary percutaneous coronary intervention for patients with delayed pre-hospital time in acute myocardial infarction

BACKGROUND Prolonged pre-hospital time for acute myocardial infarction (AMI) is associated with decreased indication for primary percutaneous coronary intervention (PCI). However, the efficacy of primary PCI in AMI patients with prolonged pre-hospital time has not been fully investigated in Japan. METHODS AND RESULTS A total of 3010 consecutive AMI patients admitted to AMI-Kyoto Multi-Center Risk Study Group hospitals were retrospectively analyzed, and the clinical characteristics and in-hospital prognosis of these patients were reviewed. Patients with pre-hospital delay [elapsed time (ET)>12 h] had a lower frequency of Killip≥3 (9.3%) and less frequently received primary PCI (77.7%) compared with patients with ET≤12 h. In the ET>12 h group, older patients or patients with MI history tended to be complicated by heart failure. Primary PCI was performed for patients with ET>12 h, irrespective of the severity of heart failure [Killip 1 (78.7%) vs Killip≥2 (74.0%); p=0.3827]. On multivariate logistic regression analysis, age [odds ratio (OR) 1.053], MI history (OR 2.860), Killip≥2 (OR 10.235), and multi-vessels or left main coronary artery as culprit (OR 11.712) were significant independent positive predictors of in-hospital mortality for patients with ET>12 h. Practice of primary PCI was not a significant negative predictor for patients with ET>12 h (OR 0.812), but it was for patients with ET≤12 h (OR 0.425). CONCLUSIONS These findings indicate that patients with ET>12 h have a less severe condition and less frequently receive primary PCI compared with patients with ET≤12 h. Although primary PCI is often performed for these patients irrespective of the severity of heart failure, no preferable effect of primary PCI on the in-hospital mortality is demonstrated. In contrary, practice of primary PCI is a significant negative predictor of in-hospital mortality for patients with ET≤12 h.