Jong Hwa Ahn

Accelerated platelet inhibition by switching from atorvastatin to a non-CYP3A4-metabolized statin in patients with high platelet reactivity (ACCEL-STATIN) study

AIMS CYP3A4-metabolized statins can influence the pharmacodynamic effect of clopidogrel. We sought to assess the impact of switching to a non-CYP3A4-metabolized statin on platelet function among patients receiving clopidogrel and atorvastatin with high on-treatment platelet reactivity (HPR). METHODS AND RESULTS Percutaneous coronary intervention (PCI)-treated patients (n= 50) with HPR [20 μM adenosine diphosphate (ADP)-induced maximal platelet aggregation (MPA) >50%] were enrolled during chronic administration of atorvastatin (10 mg/day) and clopidogrel (75 mg/day) (≥6 months). They were randomly assigned to a 15-day therapy with either rosuvastatin 10 mg/day (n= 25) or pravastatin 20 mg/day (n= 25). Platelet function was assessed before and after switching by conventional aggregometry and the VerifyNow P2Y12 assay. Genotyping was performed for CYP2C19*2/*3, CYP3A5*3, and ABCB1 C3435T alleles. The primary endpoint was the absolute change in 20 μM ADP-induced MPA. After switching, MPAs after stimuli with 20 and 5 μM ADP were decreased by 6.6% (95% confidence interval: 3.2-10.1%; P < 0.001), and 6.3% (95% confidence interval: 2.5-10.2%; P = 0.002), respectively. Fifty-two P2Y12 reaction units fell (95% confidence interval: 35-70; P < 0.001) and the prevalence of HPR decreased (24%; P < 0.001). Pharmacodynamic effects were similar after rosuvastatin and pravastatin therapy. In addition to smoking status, the combination of calcium channel blocker usage and ABCB1 C3435T genotype significantly affected the change of 20 μM ADP-induced MPA. CONCLUSIONS Among PCI-treated patients with HPR during co-administration of clopidogrel and atorvastatin, switching to a non-CYP3A4-metabolized statin can significantly decrease platelet reactivity and the prevalence of HPR. This switching effect appears similar irrespective of the type of non-CYP3A4-metabolized statin.

Novel role of platelet reactivity in adverse left ventricular remodelling after ST-segment elevation myocardial infarction: The REMODELING Trial

The role of platelet-leukocyte interaction in the infarct myocardium still remains unveiled. We aimed to determine the linkage of platelet activation to post-infarct left ventricular remodelling (LVR) process. REMODELING was a prospective, observational, cohort trial including patients (n = 150) with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. Patients were given aspirin plus clopidogrel therapy (600 mg loading and 75 mg daily). Platelet reactivity (PRU: P2Y12 Reaction Units) was assessed with VerifyNow P2Y12 assay on admission. Transthoracic echocardiography was performed on admission and at one-month follow-up. The primary endpoint was the incidence of LVR according to PRU-based quartile distribution. LVR was defined as a relative ≥ 20 % increase in LV end-diastolic volume (LVEDV) between measurements. Adverse LVR was observed in 36 patients (24.0 %). According to PRU quartile, LVR rate was 10.8 % in the first, 23.1 % in the second, 27.0 % in the third, and 35.1 % in the fourth (p = 0.015): the optimal cut-off of PRU was ≥ 248 (area under curve: 0.643; 95 % confidence interval: 0.543 to 0.744; p = 0.010). LVR rate also increased proportionally according to the level of high sensitivity-C reactive protein (hs-CRP) (p = 0.012). In multivariate analysis, the combination of PRU (≥ 248) and hs-CRP (≥ 1.4 mg/l) significantly increased the predictive value for LVR occurrence by about 21-fold. In conclusion, enhanced levels of platelet activation and inflammation determined the incidence of adverse LVR after STEMI. Combining the measurements of these risk factors increased risk discrimination of LVR. The role of intensified antiplatelet or anti-inflammatory therapy in post-infarct LVR process deserves further study.

Influence of platelet reactivity on BARC classification in East Asian patients undergoing percutaneous coronary intervention. Results of the ACCEL-BLEED study.

An increasing body of data suggests that East Asian patients have differing risk profiles for both thrombophilia and bleeding compared with Western population. This study was designed to evaluate the relationship of bleeding to platelet function in East Asians undergoing percutaneous coronary intervention (PCI). Patients who had undergone uneventful PCI (n= 301) were prospectively enrolled and bleeding events were evaluated during dual antiplatelet therapy (DAPT) with aspirin and clopidogrel. Platelet function was measured during hospitalisation and at 30-day follow-up by light transmittance aggregometry (LTA) and vasodilator-stimulated phosphoprotein phosphorylation (VASP-P) assay. During 30-day follow-up, 29.2 % of patients (n= 88) experienced post-discharge Bleeding Academic Research Consortium (BARC) complications (24.6 % and 7.0 % of BARC type 1 and 2, respectively). Patients presenting with acute myocardial infarction had fewer episodes of type 1 BARC bleeding (odds ratio: 0.41; 95 % confidence interval: 0.22 to 0.76; p= 0.005). The cut-off of low platelet reactivity (LPR) (20 µM ADP-induced platelet aggregation ≤ 46.1 %; platelet reactivity index ≤ 45.1 %) was the independent determinant of type 2 BARC bleeding (odds ratio: 3.55 and 4.44; p= 0.009 and 0.002, respectively). The first 30-day BARC bleeding episodes were associated with an increased rate of subsequent premature DAPT discontinuation during one-year follow-up (4.7 % vs 11.4 %; odds ratio: 2.60; 95 % confidence interval: 1.04 to 6.50; p= 0.035). In conclusion, among East Asians, mild bleeding episodes are common early after PCI and are associated with premature DAPT discontinuation. Type 2 BARC bleeding episodes are associated with LPR cut-offs measured at 30 days post-discharge.

Effects of Peroxisome Proliferator-Activated Receptor-δ Agonist on Cardiac Healing after Myocardial Infarction

Peroxisome proliferator-activated receptor-delta (PPAR-δ)-dependent signaling is associated with rapid wound healing in the skin. Here, we investigated the therapeutic effects of PPAR-δ-agonist treatment on cardiac healing in post-myocardial infarction (MI) rats. Animals were assigned to the following groups: sham-operated control group, left anterior descending coronary artery ligation (MI) group, or MI with administration of the PPAR-δ agonist GW610742 group. GW610742 (1 mg/kg) was administrated intraperitoneally after the operation and repeated every 3 days. Echocardiographic data showed no differences between the two groups in terms of cardiac function and remodeling until 4 weeks. However, the degrees of angiogenesis and fibrosis after MI were significantly higher in the GW610742-treated rats than in the untreated MI rats at 1 week following MI, which changes were not different at 2 weeks after MI. Naturally, PPAR-δ expression in infarcted myocardium was highest increased in 3 day after MI and then disappeared in 14 day after MI. GW610742 increased myofibroblast differentiation and transforming growth factor-beta 2 expression in the infarct zone at 7 days after MI. GW610742 also increased bone marrow-derived mesenchymal stem cell (MSC) recruitment in whole myocardium, and increased serum platelet-derived growth factor B, stromal-derived factor-1 alpha, and matrix metallopeptidase 9 levels at day 3 after MI. PPAR-δ agonists treatment have the temporal effect on early fibrosis of infarcted myocardium, which might not sustain the functional and structural beneficial effect.

Effect of adjunctive dipyridamole to DAPT on platelet function profiles in stented patients with high platelet reactivity. The result of the ACCEL-DIP Study.

Adjunctive use of phosphodiesterase (PDE) inhibitor can enhance antiplatelet and vasoprotective properties in patients with cardiovascular disease. The aim of this study was to evaluate the impact of PDE5 inhibitor dipyridamole on platelet function in stented patients with high platelet reactivity (HPR) during dual antiplatelet therapy (DAPT) with aspirin and clopidogrel. Patients with HPR after 600-mg clopidogrel loading were randomly assigned to adjunctive dipyridamole 75 mg twice daily to standard DAPT (DIP group; n = 45) or double-dose clopidogrel of 150 mg daily (DOUBLE group; n = 46) for 30 days. Platelet function was assessed at baseline and 30-day follow-up with platelet reactivity index (PRI) by vasodilator-stimulated phosphoprotein-phosphorylation (VASP-P) assay and platelet aggregation (PA) by light transmittance aggregometry (LTA). Primary endpoint was PRI at 30-day follow-up. HPR was defined as PRI > 50%. Baseline platelet function did not differ between the groups. Following 30-day therapy, platelet function was significantly reduced in the DIP and DOUBLE groups (all p-values ≤ 0.004 and ≤ 0.068, respectively). PRI values were not significantly different between the two groups (mean difference: 3.1%; 95% confidence interval: -2.8% to 9.0%: p = 0.295). PA values and prevalence of HPR were similar between the groups. However, a significant number of patients still exhibited HPR in the DIP (75.6%) and DOUBLE (67.4%) groups. In conclusion, among stented HPR patients, adding dipyridamole to DAPT does not reduce platelet reactivity and prevalence of HPR compared with double-dose clopidogrel therapy, and therefore both strategies are inadequate to overcome HPR.

Long-term Prognosis and Clinical Characteristics of Patients with Newly Diagnosed Diabetes Mellitus Detected after First Acute Myocardial Infarction: from KAMIR-NIH Registry

Background and Objectives After the first acute myocardial infarction (AMI), a considerable proportion of patients are newly diagnosed with diabetes mellitus (DM). However, in AMI, controversy remains regarding the disparity in prognosis between previously diagnosed DM (known-DM) and newly diagnosed DM (new-DM). Methods The study included 10,455 patients with AMI (non-DM, 6,236; new-DM, 659; known-DM, 3,560) admitted to one of 15 participating centers in Korea between November 2011 and January 2016 (average follow-up, 523 days). We compared the characteristics and clinical course of patients with known-DM and those with new- or non-DM. Results Compared to patients with known-DM, those with new-DM or non-DM were younger, more likely to be male, and less likely to have hypertension, dyslipidemia, prior stroke, angina, or myocardial infarction. Compared to patients with new-DM or non-DM (reference), those with known-DM had higher risks of major adverse cardiac events (hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.06–1.35; p=0.004), cardiac death (HR, 1.26; 95% CI, 1.01–1.57; p=0.042), and congestive heart failure (HR, 1.58; 95% CI, 1.20–2.08). Unlike known-DM, new-DM did not increase the risk of cardiac events (including death). Conclusions Known-DM was associated with a significantly higher risk of cardiovascular events after AMI, while new-DM had a similar risk of cardiac events as that noted for non-DM. There were different cardiovascular outcomes according to diabetes status in patients with AMI.

Prognostic value of total triiodothyronine and free thyroxine levels for the heart failure in patients with acute myocardial infarction

Background/Aims Although a low triiodothyronine (T3) state is closely associated with heart failure (HF), it is uncertain whether total T3 levels on admission is correlated with the clinical outcomes of acute myocardial infarction (AMI). The aim of this study is to investigate the prognostic value of total T3 levels for major adverse cardiovascular and cerebrovascular events (MACCEs) in patients with AMI undergone percutaneous coronary intervention (PCI). Methods A total of 765 PCI-treated AMI patients (65.4 ± 12.6 years old, 215 women) between January 2012 and July 2014 were included and 1-year MACCEs were analyzed. We assessed the correlation of total T3 and free thyroxine (fT4) with prevalence of 1-year MACCEs and the predictive values of total T3, fT4, and the ratio of total T3 to fT4 (T3/fT4), especially for HF requiring re-hospitalization. Results Thirty patients (3.9%) were re-hospitalized within 12 months to control HF symptoms. Total T3 levels were lower in the HF group than in the non-HF group (84.32 ± 21.04 ng/dL vs. 101.20 ± 20.30 ng/dL, p < 0.001). Receiver operating characteristic curve analysis showed the cut-offs of total T3 levels (≤ 85 ng/dL) and T3/fT4 (≤ 60) for HF (area under curve [AUC] = 0.734, p < 0.001; AUC = 0.774, p < 0.001, respectively). In multivariate analysis, lower T3/fT4 was an independent predictor for 1-year HF in PCI-treated AMI patients (odds ratio, 1.035; 95% confidential interval, 1.007 to 1.064; p = 0.015). Conclusions Lower levels of total T3 were well correlated with 1-year HF in PCI-treated AMI patients. The T3/fT4 levels can be an additional marker to predict HF.

Isolated Left Ventricular Noncompaction with a Congenital Aneurysm Presenting with Recurrent Embolism

Isolated left ventricular noncompaction (LVNC) is a rare disorder caused by embryonic arrest of compaction. LVNC is sometimes associated with other congenital cardiac disorders; however, there have been few reports of its coexistence with a left ventricular aneurysm. A 40-year-old woman was admitted to our hospital for renal infarction. She had a history of embolic cerebral infarction 10 years ago. Transthoracic echocardiography showed prominent trabeculae and deep intertrabecular recesses which are filled with blood from the left ventricular (LV) cavity. A thrombus in the akinetic apical wall was confirmed by contrast echocardiography. Using cardiac computed tomography and magnetic resonance imaging, we rejected a possible diagnosis of suspicion of coronary artery disease. She was diagnosed LVNC with a thrombus in apical aneurysm. Here, we report the first patient in Korea known to have LVNC accompanying LV congenital aneurysm presenting with recurrent embolism.

Prognostic value of brachial-ankle pulse wave velocity in patients with non-st-elevation myocardial infarction

Objective Brachial-ankle pulse wave velocity (baPWV) measurement is a well-established modality for assessing arterial stiffness and predicting cardiovascular events. However, to our knowledge, its usefulness has not been clarified among patients with non-ST-elevation myocardial infarction (NSTEMI). This study assessed the prognostic value of baPWV in patients with NSTEMI. Patients and methods Patients (n=411, mean age, 63.8±13.5 years, 75.2% men) with NSTEMI who underwent a percutaneous coronary intervention and baPWV measurement were recruited between January 2013 and December 2015. Cardiac mortality and major adverse cardiovascular events (MACE) including cardiac death, re-acute myocardial infarction, revascularization, heart failure, and stroke after discharge were analyzed. The mean follow-up duration was 350 days. Results MACE and cardiac mortality occurred in 26 (6.3%) patients and 13 (3.1%) patients. Kaplan–Meier survival curves showed that MACE and cardiac mortality were significantly higher in patients with high baPWV (1708.0 cm/s). In multivariable Cox regression analysis, high baPWV (hazard ratio: 2.55; 95% confidence interval: 1.03–6.30, P=0.043) was an independent predictor of MACE even after adjusting for possible confounders. Conclusion Our findings indicate that baPWV was a strong independent prognostic factor of MACE in patients with NSTEMI. This suggests that baPWV can be a useful prognostic factor in the clinical setting for easier and less invasive prediction of MACE in patients with NSTEMI.

Blood-Pressure and Cholesterol Lowering in the HOPE-3 Trial.

To the Editor: In their article on the Heart Outcomes Prevention Evaluation (HOPE)–3 trial, Lonn et al. (May 26 issue)1 report that among patients at intermediate risk, intensified antihypertensive therapy was not associated with a lower rate of cardiovascular events than the rate among patients who received placebo. These findings appear to contrast with the results of the Systolic Blood Pressure Intervention Trial (SPRINT),2 in which intensive treatment (systolic blood-pressure target, <120 mm Hg), as compared with standard treatment (systolic blood-pressure target, <140 mm Hg) reduced the rates of cardiovascular events and death from any cause. The HOPE-3 investigators explain this difference as being a consequence of higher baseline risk and greater blood-pressure reduction in SPRINT than in the HOPE-3 trial. We consider the method of blood-pressure measurement to be an alternative explanation. In the HOPE-3 trial, conventional blood-pressure measurements at an office visit (hereafter referred to as office blood pressure) were used, whereas unattended, automated, office blood-pressure measurements were used in SPRINT.3 To substantiate this hypothesis, we recruited 29 patients who met the inclusion and exclusion criteria of SPRINT. Office blood pressure was measured after 5 minutes of rest; subsequently, the observer left the room, and automated office blood pressure was measured 5 minutes later, as in SPRINT. The systolic blood pressure was 12.6 mm Hg higher and the diastolic blood pressure was 3.6 mm Hg higher with office bloodpressure measurement than with automated office blood-pressure measurement. The average systolic blood pressure (134 mm Hg) with office blood-pressure measurement among patients in the placebo group of the HOPE-3 trial may thus correspond to an automated office blood pressure that is close to 120 mm Hg. This is similar to the average systolic blood pressure in the intensive-treatment group in SPRINT.