Evaluation of metoprolol standard dosing pathway in Chinese patients with acute coronary syndrome: a prospective multicenter single-arm interventional study / 老年心脏病学杂志（英文版）

OBJECTIVE@#To evaluate the feasibility and tolerability of metoprolol standard dosing pathway (MSDP) in Chinese patients with acute coronary syndrome (ACS).@*METHODS@#In this multicenter, prospective, open label, single-arm and interventional study that was conducted from February 2018 to April 2019 in fifteen Chinese hospitals. A total of 998 hospitalized patients aged ≥ 18 years and diagnosed with ACS were included. The MSDP was applied to all eligible ACS patients based on the standard treatment recommended by international guidelines. The primary endpoint was the percentage of patients achieving the target dose at discharge (V2). The secondary endpoints included the heart rate and blood pressure at V2 and four weeks after discharge (V4), and percentage of patients experiencing bradycardia (heart rate < 50 beats/min), hypotension (blood pressure < 90/60 mmHg) and transient cardiac dysfunction at V2 and V4.@*RESULTS@#Of the 998 patients, 29.46% of patients achieved the target dose (≥ 95 mg/d) at V2. The total population was divided into two groups: target group (patients achieving the target dose at V2) and non-target group (patients not achieving the target dose at V2). There was significant difference in the reduction of heart rate from baseline to discharge in the two groups (-4.97 ± 11.90 beats/min vs. -2.70 ± 9.47 beats/min, P = 0.034). There was no significant difference in the proportion of bradycardia that occurred in the two groups at V2 (0 vs. 0, P = 1.000) and V4 (0.81% vs. 0.33%, P = 0.715). There was no significant difference in the proportion of hypotension between the two groups at V2 (0.004% vs. 0.004%, P = 1.000) and V4 (0 vs. 0.005%, P = 0.560). No transient cardiac dysfunction occurred in two groups during the study. A total of five adverse events (1.70%) and one serious adverse event (0.34%) were related to the pathway in target group.@*CONCLUSIONS@#In Chinese ACS patients, the feasibility and tolerability of the MSDP have been proved to be acceptable.

Microvascular Integrity and Ventricular Function according to Early ST-Segment Resolution in Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES: Early resolution of ST-segment elevation improves the short and long-term mortalities in acute myocardial infarction (AMI). However, the correlations between the ST segment resolution and microvascular integrity, or functional recovery of the left ventricle, were not explored. SUBJECTS AND METHODS: The study population consisted of 42 AMI patients who received thrombolytic therapy (35 male, 54+/-11 years) and consecutive successful percutaneous coronary intervention (PCI) (<30% of residual stenosis, recovered TIMI 3 flow) within 7 days. The coronary flow reserve (CFR) was measured at the segment just distal to the angioplasty site using intracoronary Doppler wire following a successful PCI. Electrocardiograms (ECG) were evaluated before, and within 90-150 minutes after, of the thrombolytic therapy. The percentage change in the ST segment resolution, from the baseline to follow-up, was categorized into complete resolution (70%, n=24), partial resolution (30% to <70%, n=10) and no resolution (0% to <30%, n=8). The ejection fraction (EF) and regional wall motion score indices (RWMSI) were assessed by 2D-echocardiography before, and following the PCI (9+/-5 months). RESULTS: Complete ST segment resolution was observed in 57%, partial resolution in 24%, and no resolution in 19% of patients. The CFR was significantly higher in the complete resolution group than in the no resolution group, and the minimal coronary vascular resistance index was significantly lower in the complete resolution group than in the no resolution group (2.1+/-0.5 vs. 1.4+/-0.4, p=0.006; 2.31+/-0.99mmHg sec cm-1 vs. 3.84+/-2.19mmHg sec cm-1, p=0.035, respectively). The changes in the EF and RWMSI were significantly better in complete resolution group than in the no resolution group (10+/-9% vs. 0+/-5%, p=0.028; -1.03+/-0.50 vs. 0.24+/-0.66, p=0.004, respectively), and the left ventricular end diastolic and systolic volume indices were significantly increased in the no resolution group at follow-up (42.0+/-14.8 mL/m2 vs. 55.8+/-18.1 mL/m2, p=0.006; 23.2+/-10.9 mL/m2 vs. 30.5+/-15.9 mL/m2, p=0.039, respectively). CONCLUSION: In the AMI patients, with a recovered TIMI 3 flow, following thrombolysis and successful elective PCI, there were differences in the coronary flow reserve according to the degree of early resolution of the ST segment. The patients with an early complete resolution of the ST segment showed the most favorable preservation of the microvascular integrities and improvement of the left ventricular function. The degree of early resolution of the ST segment might be a useful indicator for the prediction of left ventricular functional changes at follow-up.

Coronary Flow Reserve as a Predictor of Long-Term Clinical Outcome after Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES: It has been shown that the coronary flow reserve (CFR) of an infarct related artery can predict left ventricular functional recovery following acute myocardial infarction (AMI). However, the prognostic value of CFR on the long-term clinical outcome of patients with an AMI has not been studied. SUBJECTS AND METHODS: Using a Doppler guide wire, we measured the CFR in 130 patients with an AMI following successful intervention (6+/-3 days after onset of the AMI). Two-year follow-up was conducted with regard to end points, including : cardiac death, non-fatal AMI, and severe congestive heart failure (CHF; > or = NYHA III). RESULTS: During the follow-ups, cardiac events occurred in 17 patients (5 deaths, 3 non-fatal AMIs and 9 severe CHFs). After analysis of the receiver operating characteristic curves, the best cut-off value for CFR in predicting cardiac events was 1.4 (sensitivity 76.5%, specificity 73.5%, accuracy 82.0%). With cardiac events as an end point, a 2-year Kaplan-Meier event survival analysis revealed that the patients with a CFR 1.4 (Event free survival rates were 69.8% vs. 95.4%, respectively, p<0.001). Using Cox proportional hazard analyses, as an independent predictor, age, heart rate, CFR and left ventricular end systolic volume index, were also found to be significantly associated with cardiac events (hazard ratios 1.1224, 1.0404, 0.1887, and 1.0588, respectively). CONCLUSION: The coronary flow reserve, of infarct related arteries, measured during the early recovery phase can be used as an independent predictor for the prognosis of patients with an acute myocardial infarction following successful intervention.

Predictors of Side Branch Occlusion Immediately after Coronary Stenting: an Intravascular Ultrasound Study

BACKGROUND AND OBJECTIVES: Previous studies have indicated that side branch occlusion (SBO) remains a significant problem in coronary bifurcation lesions during percutaneous intervention. SUBJECTS AND METHODS: To evaluate the predictors of SBO by intravascular ultrasound (IVUS), 35 patients (28 males, mean age 56+/-11 years) were studied at their left anterior descending artery (LAD)-diagonal branch (DB) bifurcation lesions, prior to coronary intervention for the measurement of the following plaque characteristics: total plaque area (PA), PA of the branch-side semicircle, % area stenosis (%AS) of the LAD, the presence of bull's eye in the DB, the diameter of the vessel and the ostial lumen of the DB, and the LAD-DB angle. SBO was defined as a persistant reduction in the TIMI flow to < OR = 1 by the end of the procedure. RESULTS: The PA of the branch-side semicircle, the vessel diameter and the ostial lumen diameter of the DB all significantly affected the SBO. The total PA and the %AS of the LAD were not related to the SBO. Multivariate analysis identified that the PA of the branch-side semicircle was the only predictor of SBO (odds ratio 3.2, 95% confidence interval 1.3 to 8.6, p=0.015). CONCLUSION: It appears that the plaque distribution of LAD is a major determinant of SBO. These findings support the theory that the plaque shift ("snow plow effect") may be the mechanism of the SBO following stenting.

Relation Between Vascular Resistance and Intimal Thickness in Patients with Coronary Artery Disease

BACKGROUND: The intimal thickening of coronary artery was understood as an early process in the beginning of atherosclerosis. However, the implication of intimal thickening as a morphologic change of coronary artery disease, on the coronary vascular hemodynamics has not been explored. METHODS: To evaluate the effect of intimal thickening on the coronary vascular hemodynamics, we studied the extent of intimal thickening on intravascular ultrasound(IVUS) and the coronary vascular flow and resistance by using Doppler wire in left anterior descending coronary arteries after successful intervention in 40 patients(29 males, mean age 55+/-9 years) with coronary artery disease. Mean intimal index and mean lumen cross sectional area were determined by IVUS and coronary flow average peak velocity was obtained by using Doppler wire before and after intracoronary adenosine in distal artery to the stenosis. Coronary flow velocity reserve(CFR), volumetric coronary blood flow(CBF) and coronary vascular resistance index(CVRI) were calculated. Hyperemic pressure-to-flow ratio(hyperemic mean aortic pressure/hyperemic volumetric coronary blood flow), ie, an index of minimal coronary vascular resistance(mCVR), was further derived. RESULTS: Intimal index(mean 20.0+/-8.3%) was significantly correlated with CVRI(mean 0.33+/-0.14, r=.37, p=.02) and mCVR(mean 0.81+/-0.40mmHg/ml/min, r=.36, p=.02). However, there was no correlation with CBF and CFR. CONCLUSION: The CVRI and mCVR(hyperemic pressure to flow ratio), the indices coronary microvascular resistance, were significantly related to the degree of intimal thickness of coronary artery. The extent of intimal thickness of coronary artery on IVUS study may be related to microvascular integrity.

The Effects of Two-Month Combination Therapy of Cilostazol and Aspirin after Intracoronary Stenting

BACKGROUND AND OBJECTIVES: It is well known that anti-platlet agents decrease the rate of subacute thrombosis after intracoronary stenting significantly. The aim of this study is to assess the antithrombotic effect and safety of 2-month combined regimen of cilostazol and aspirin on intracoronary stenting. METHODS: The study population consisted of 78 lesions of 57 patients (age: 58.1+/-10.3, male 47, female 10) with ischemic heart disease who were underwent successful intracoronary stenting. They were received cilostazol(200mg/day) and aspirin(100mg/day) two days before intracoronary stenting and continued for 8 weeks, and then aspirin was medicated continuously during the study. The laboratory and clinical findings were evaluated before cilostazol administration, 4 weeks, 8 weeks and 6 months after intervention. The excercise treadmill test was done at 6 months after intervention. RESULTS: Subacute thrombosis occurred in 2 patients(3.5%). Target lesion revascularization(TLR) was done in 4 patients(7.3%). Clinical restenosis (symptomatic or positive stress test, subacute thrombosis and TLR) occurred in 15 patients(26.3%). There was no granulocytopenia, or severe liver dysfunction. HDL-cholesterol was increased significantly at 2 months(36.6+/-7.4 mg/dl versus 41.6+/-9.3 mg/dl. p<0.01) and 6 months(36.6+/-7.4 mg/dl versus 42.4+/-10.6 mg/dl. p<0.01) follow up. CONCLUSION: Two-month combined regimen of cilostazol and aspirin was effective and safe after intracoronary stenting. Subacute thrombosis and clinical restenosis rate were comparable with pervious reports. Further large randomized trials are needed for the evaluation of favorable effect of cilostazol on lipid metabolism.

The Effects of Two-Month Combination Therapy of Cilostazol and Aspirin after Intracoronary Stenting

BACKGROUND AND OBJECTIVES: It is well known that anti-platlet agents decrease the rate of subacute thrombosis after intracoronary stenting significantly. The aim of this study is to assess the antithrombotic effect and safety of 2-month combined regimen of cilostazol and aspirin on intracoronary stenting. METHODS: The study population consisted of 78 lesions of 57 patients (age: 58.1+/-10.3, male 47, female 10) with ischemic heart disease who were underwent successful intracoronary stenting. They were received cilostazol(200mg/day) and aspirin(100mg/day) two days before intracoronary stenting and continued for 8 weeks, and then aspirin was medicated continuously during the study. The laboratory and clinical findings were evaluated before cilostazol administration, 4 weeks, 8 weeks and 6 months after intervention. The excercise treadmill test was done at 6 months after intervention. RESULTS: Subacute thrombosis occurred in 2 patients(3.5%). Target lesion revascularization(TLR) was done in 4 patients(7.3%). Clinical restenosis (symptomatic or positive stress test, subacute thrombosis and TLR) occurred in 15 patients(26.3%). There was no granulocytopenia, or severe liver dysfunction. HDL-cholesterol was increased significantly at 2 months(36.6+/-7.4 mg/dl versus 41.6+/-9.3 mg/dl. p<0.01) and 6 months(36.6+/-7.4 mg/dl versus 42.4+/-10.6 mg/dl. p<0.01) follow up. CONCLUSION: Two-month combined regimen of cilostazol and aspirin was effective and safe after intracoronary stenting. Subacute thrombosis and clinical restenosis rate were comparable with pervious reports. Further large randomized trials are needed for the evaluation of favorable effect of cilostazol on lipid metabolism.

Assessment of coronary artery stenosis with intracoronary Doppler guide wire and modified continuity equation method ; A comparison with dipyridamole stress Thallium-201 SPECT

BACKGROUND: Previous studies of animal and human experiments have shown excellent correlation between true or angiographic stenosis severity and stenosis severity calculated from intracoronary Doppler flow measurements and continuity equation method. However, there remains practical problems to be solved on its clinical application. To minimize these problems, the concept of modified continuity equation method, calculating the percent area stenosis by comparing the maximal in-stenosis flow velocity to the distal reference flow velocity, was introduced and compared with dipyridamole stress thallium-201 SPECT. METHODS: In this prospective study, 102 patients (mean age 57+/-10 years, 69 men, 33 women) with coronary artery stenoses ranging from 23-89% in percent diameter stenosis, who received coronary angiography, dipyridamole stress thallium-201 SPECT, and successful intracoronary flow velocity measurements were included. Modified continuity equation method and distal coronary flow velocity reserve were compared to the result of dipyridamole stress thallium-201 SPECT and quantitative coronary angiography. RESULTS: Measurements of adequate intralesional and stenosis distal flow velocities were successful in 102 out of 106 stenoses (96%). Minimal luminal area and percent area stenosis calculated from modified continuity equation method showed significant correlations with those of quantitative coronary angiography. Modified continuity equation method significantly underestimated the severity of stenosis than quantitative coronary angiography did. The test accuracy in relation to the result of dipyridamole stress thallium-201 SPECT were 91% in modified continuity equation method, 80% in quantitative coronary angiography and 63% in distal coronary flow velocity reserve. CONCLUSION: Application of intracoronary Doppler guide wire and modified continuity equation method appears to provide useful on-site implications for the anatomic and functional assessment of coronary artery stenosis. The modified continuity equation method would be one of the promising concepts for clinical decision making during coronary interventions.