Coronary Flow In Patients Research Articles

The effect of blood cell count on coronary flow in patients with coronary slow flow phenomenon

Objective The coronary slow flow phenomenon(CSFP)is a coronary artery disease with a benign course, but its pathological mechanisms are not yet fully understood. The purpose of this controlled study was to investigate the cellular content of blood in patients diagnosed with CSFP and the relationship of this with coronary flow rates. Methods Coronary angiographies of 3368 patients were selected to assess thrombolysis in myocardial infarction(TIMI) frame count(TFC) values. Seventy eight of them had CSFP, and their demographic and laboratory findings were compared with 61 patients with normal coronary flow. Results Patients'demographic characteristics were similar in both two groups. Mean corrected TFC(c TFC) values were significantly elevated in CSFP patients(P< 0.001). Furthermore, hematocrit and hemoglobin values, and eosinophil and basophil counts of the CSFP patients were significantly elevated compared with the values obtained in the control group(P= 0.005,P= 0.047,P= 0.001 and P= 0.002). The increase observed in hematocrit and eosinophil levels showed significant correlations with increased TFC values(r= 0.288 and r= 0.217). Conclusion Significant changes have been observed in the cellular composition of blood in patients diagnosed with CSFP as compared to the patients with normal coronary blood flow. The increases inhematocrit levels and in the eosinophil and basophil counts may have direct or indirect effects on the rate of coronary blood flow. Key words: Basophil; Eosinophil; Hematocrit; Hemoglobin; Coronary slow flow

Effects of patients anxiety and depression scores on coronary flow in patients with normal coronary arteries

a Dr A.Y. Ankara Oncology Training and Research Hospital, Psychiatry Clinic, Ankara, Turkey b Bolu Izzet Baysal University Medical Faculty, Department of Cardiology, Bolu, Turkey c Trakya University Medical Faculty, Department of Cardiology, Edirne, Turkey d Izmir University Medical Faculty, Medicalpark Hospital, Department of Cardiology, Izmir, Turkey e Middle East Hospital, Division of Cardiology, Mersin, Turkey

Coronary Blood Flow in Patients With Severe Aortic Stenosis Before and After Transcatheter Aortic Valve Implantation

Patients with severe aortic stenosis and no obstructed coronary arteries are reported to have reduced coronary flow. Doppler evaluation of proximal coronary flow is feasible using transesophageal echocardiography. The present study aimed to assess the change in coronary flow in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI). The left main coronary artery was visualized using transesophageal echocardiography in 90 patients undergoing TAVI using the Edwards SAPIEN valve. The peak systolic and diastolic velocities of the coronary flow and the time-velocity integral were obtained before and after TAVI using pulse-wave Doppler. Mean aortic gradients decreased from 47.1 ± 15.7 mm Hg before TAVI to 3.6 ± 2.6 mm Hg after TAVI (p <0.001). The aortic valve area increased from 0.58 ± 0.17 to 1.99 ± 0.35 cm(2) (p <0.001). The cardiac output increased from 3.4 ± 1.1 to 3.8 ± 1.0 L/min (p <0.001). Left ventricular end-diastolic pressure (LVEDP) decreased from 19.8 ± 5.4 to 17.3 ± 4.1 mm Hg (p <0.001). The following coronary flow parameters increased significantly after TAVI: peak systolic velocity 24.2 ± 9.3 to 30.5 ± 14.9 cm/s (p <0.001), peak diastolic velocity 49.8 ± 16.9 to 53.7 ± 22.3 cm/s (p = 0.04), total velocity-time integral 26.7 ± 10.5 to 29.7 ± 14.1 cm (p = 0.002), and systolic velocity-time integral 6.1 ± 3.7 to 7.7 ± 5.0 cm (p = 0.001). Diastolic time-velocity integral increased from 20.6 ± 8.7 to 22.0 ± 10.1 cm (p = 0.04). Total velocity-time integral increased >10% in 43 patients (47.2%). Pearson's correlation coefficient revealed the change in LVEDP as the best correlate of change in coronary flow (R = -0.41, p = 0.003). In conclusion, TAVI resulted in a significant increase in coronary flow. The change in coronary flow was associated mostly with a decrease in LVEDP.

OP-005 Relation Between Platelet/Lymphocyte Ratio and Coronary Flow in Patients With ST-Segment Elevation Acute Myocardial Infarction Undergoing Primary Coronary Intervention

Platelet/lymphocyte ratio (PLR) has been shown as an inflammatory biomarkers for coronary heart disease, but data regarding the association of PLR with coronary blood flow in ST-segment elevation myocardial infarction (STEMI) are lacking. We aimed to investigate the relationship between the PLR and no-reflow in patient with STEMI. In present study, we included 360 consecutive patients suffering from STEMI who underwent primary percutaneous coronary intervention (p-PCI), reperfused within 12 h of symptom onset. Patients were divided into 2 groups based on Thrombolysis In Myocardial Infarction (TIMI) flow Grade and Myocardial blush grade (MBG). No-reflow after p-PCI was defined as a coronary TIMI flow grade <= 2 after vessel re-canalized or TIMI flow grade 3 together with a final MBG < 2. The PLR values were significantly higher in patients with no-reflow than in those without no-reflow (283.7 ± 96.6 vs 251.8 ± 75.6 p <0.001). In regression analysis, PLR [odds ratio 1.18, 95% confidence interval (CI) 1.05-1.39; P <0.001]. In receiver operator characteristic curve analysis, optimal cut-off value of PLR to predict no-reflow was found as 162, with 70% sensitivity and 61% specificity. Furthermore, we found that a significant correlation between the PLR both the TIMI thrombus grade scale and C-reactive protein (r = 42, p <0.001 and r = 33, p <0.001, respectively). PLR on admission is a strong and independent predictor of poor coronary blood flow following p-PCI in patient with STEMI. This simple and readily avaible parameter may be a useful biomarker for stratification of risk in patients with STEMI.

Association of Glomerular Filtration Rate With Slow Coronary Flow in Patients With Normal to Mildly Impaired Renal Function

We evaluated the association between estimated glomerular filtration rate (eGFR) and slow coronary flow (SCF) in patients with normal to mildly impaired renal function; 211 patients with angiographically proven SCF and 219 controls were studied. Patients were categorized based on the angiographic findings as with or without SCF. We used the Modification of Diet in Renal Disease equation to calculate eGFR. The frequency of mildly decreased eGFR, serum uric acid levels, and eGFR was higher in the SCF group. Patients with mildly impaired renal function had higher thrombolysis in myocardial infarction frame counts in 3 major coronary arteries. In logistic regression analysis, uric acid (odds ratio [OR] = 1.323, 95% confidence interval [CI] = 1.109-1.572, P = .002) and eGFR (OR = 0.972, 95% CI = 0.957-0.987, P < .001) were independent correlates of SCF. In conclusion, eGFR was significantly correlated with SCF in patients with normal to mildly impaired renal function.

Association Between Intraprocedural Thrombotic Events and Adverse Outcomes After Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction (a Harmonizing Outcomes With RevasculariZatiON and Stents in Acute Myocardial Infarction [HORIZONS-AMI] Substudy)

The present study sought to determine the extent to which adverse angiographic events encountered during percutaneous coronary intervention for ST-segment elevation myocardial infarction (STEMI) are associated with adverse clinical outcomes. Patients with STEMI represent a cohort at particularly high risk of intraprocedural thrombotic events (IPTEs). The overall frequency and implications of IPTEs occurring in patients with STEMI have not been systematically quantified in previous studies. A total of 3,163 patients undergoing primary percutaneous coronary intervention with stent implantation for STEMI in the Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial underwent detailed frame-by-frame core laboratory angiographic analysis to assess IPTEs. The clinical outcomes at 30 days were compared between the patients with and without IPTEs. IPTEs, defined as the development of new or increasing thrombus, abrupt vessel closure, no reflow, slow reflow, and distal embolization at any point during the procedure, occurred in 386 patients (12.2%). The independent predictors of IPTE were thrombus at baseline, lesion length, and randomization to bivalirudin; the patients with IPTEs were also more likely to receive bailout glycoprotein IIb/IIIa inhibitors and unplanned thrombectomy. Compared with patients without IPTEs, the patients with IPTEs had higher 30-day rates of composite major adverse cardiovascular events (death, myocardial infarction, ischemic target vessel revascularization, and stroke; 7.8% vs 4.2%, p = 0.002), major bleeding not related to coronary artery bypass grafting (11.8% vs 6.5%, p <0.001), and all-cause death (4.2% vs 1.8%, p = 0.002). On multivariate analysis, IPTEs were independently associated with 30-day major adverse cardiovascular events, major bleeding, and death. In conclusion, the development of IPTEs in patients undergoing primary percutaneous coronary intervention for STEMI was associated with subsequent adverse outcomes, including major adverse cardiovascular events, major bleeding, and death. Additional studies of strategies to decrease the occurrence of IPTEs are warranted.

Lipoprotein-phospholipase A2 is associated with increased arterial stiffness and abnormal wave reflections linked with impaired coronary flow in patients with CAD

Lipoprotein phospholipase A2 (Lp-PLA2) is an emerging inflammatory marker with prognostic value. Aortic wall properties and wave reflections determine coronary perfusion, LV function and have an independent prognostic value. We investigated the association of Lp-PLA2 with arterial stiffness and abnormal wave reflections in CAD patients. Methods: We assessed in 70 patients with angiographically documented CAD. We measured pulse wave velocity using both the Complior (carotid to femoral-PWVc) and Arteriograph apparatus (PWVa-oscillometric method). By means of pulse wave analysis (Arteriograph apparatus) we calculated the augmentation index (AI) of the arterial wave reflection, the diastolic area (DAI%) of the aortic pulse wave and diastolic reflection area (DRA), an index of diastolic filling of coronary arteries derived by duration of diastole and area between the expected area of the diastolic pressure curve without wave reflection and the true area with wave reflection. Patients were also categorised into 2 subgroups according to the median values of the pulse wave analysis indices. The velocity time integral of the diastolic component of coronary flow of the LAD was assessed using Doppler echocardiography Results: Increasing levels of Lp-PLA2 were related with smoking, increasing PWVc, PWVa, AI and decreasing DAI% and DRA (r=0.41, r=-0.31, r=-0.45 and r=0.38 r=0.47, respectively, p 10 m/sec than in those with PWVa 34% than in those with AI 45% (138±36 vs. 97±40 pg/ml, p=0.015) and in patients with DRA 43 (141±36 vs. 99±40 pg/ml, p=0.01). Patients with PWVc>11 m/sec had also higher Lp-PLA2 those with PWVc <11 m/sec (171±49 vs. 119±26 pg/ml, p=0.003).A reduced resting coronary flow velocity time integral was related with reduced DAI% and DRA (r=0.36, r=0.40, p<0.05). Conclusions: Increasing levels of Lp-PLA2 are related to impaired aortic wall properties and abnormal wave reflections associated with impaired coronary diastolic filling. This finding suggests a potential role for Lp-PLA2 to identify CAD patients with adverse prognosis.

Impact of Anticoagulation on Coronary Flow in Patients With Non-ST Elevation Acute Coronary Syndrome

The effect of anticoagulation by heparin on patients with non-ST elevation acute coronary syndrome (NSTE-ACS), receiving early dual antiplatelet therapy, has not been fully evaluated. We classified 355 patients with NSTE-ACS according to the adequacy of anticoagulation (percentage of low activated partial thromboplastin time [APTT] level). The 6-hour APTT level was optimal in only 23.1% of the patients treated with unfractionated heparin. The rate of poor preprocedural coronary blood flow (thrombolysis in myocardial infarction grade <3, 39.1%, 30.5%, 30.3%, and 33.9% in the 100% low-, 99%∼50% low-, 49%∼1% low-, and 0% low-APTT group, respectively, P = .632) and bleeding events did not differ between the groups. Instead, in multivariate analysis, the diagnosis of myocardial infarction was the only independent predictor of poor coronary flow. For bleeding events, the usage of glycoprotein IIb/IIIa inhibitor appeared to be a sole risk factor. In conclusion, inadequate preprocedural anticoagulation was not associated with adverse outcomes in patients with NSTE-ACS treated with dual antiplatelet agents.

Intracoronary glycoprotein IIb/IIIa inhibitor infusion via a perfusion coronary catheter to decrease thrombus burden: Results from the ClearWay™ Multicenter Registry

This multicenter registry aimed to assess the ClearWay™ (CW) perfusion catheter in reduction of thrombus burden and improvement of the coronary flow during percutaneous coronary intervention (PCI). The presence or development of thrombus during PCI is associated with poor prognosis. The utility of the CW perfusion catheter was assessed in patients who presented with intracoronary thrombus and were subjected to PCI. Data were collected by online survey from 15 US sites. Angiographic assessment of the coronary thrombus burden and the coronary flow after intracoronary infusion of glycoprotein (GP) IIb/IIIa inhibitors via the CW catheter was evaluated at baseline, immediately after infusion, and at the end of the procedure. The cohort included 102 patients; 71.6% presented with ST-elevation myocardial infarction (MI), 21.6% with non-ST-elevation MI, 5.9% with stable angina pectoris, and 2.9% with silent ischemia. The mean cohort age was 59.9±14.5years and comprised mostly of men (72.5%). GP IIb/IIIa inhibitors were infused via the CW catheter on average 1.1±0.3 times, with a mean pressure of 4.2±2.7atm and a mean infusion time of 55±55s. Following the infusion, Thrombolysis In Myocardial Infarction (TIMI) flow improved by 1° in 71 patients (69.6%) and by 2° in 51 patients (50%), while visible thrombus was reduced by 52% (p<0.001). In the final angiogram, TIMI flow was restored in 90.2% and clearance of a visible thrombus was obtained in 91.8% of the lesions. Intracoronary infusion of GP IIb/IIIa inhibitors via the perfusion CW catheter is associated with significant reduction in thrombus burden and with improvement of the coronary flow in patients presenting or developing thrombus burden during PCI.

Correlation of serum uric acid levels with coronary flow in patients with ST-segment elevation myocardial infarction undergoing primary coronary intervention

To explore the association of the uric acid levels and coronary blood flow in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). A total of 276 STEMI patients undergoing primary PCI were enrolled and divided into 2 groups based upon the Thrombolysis in Myocardial Infarction (TIMI) flow grade. No-reflow was defined as TIMI Grade 0, 1 and 2 flows. The association of uric acid levels on admission with TIMI flow grade after PCI was assessed by multivariate Logistic regression. Major adverse cardiac events (MACE) were defined as death, non-fatal myocardial infarction and need for repeat percutaneous revascularization or coronary artery bypass grafting. The uric acid level was significantly higher in the no-reflow group (n = 57) than that of the normal-flow group (n = 219, 372 ± 111 vs 303 ± 102, P < 0.01). In-hospital MACEs were significantly higher in the patients with no reflow (8.8% vs 1.8%, P = 0.016). A uric acid level ≥ 345 mmol/L measured on admission had a 61.2% sensitivity and 77.5% specificity in predicting no-reflow at ROC curve analysis. At multivariate analyses, high plasma uric acid (OR 1.01, 95%CI 1.01 - 1.01, P < 0.01), neutrophil count (OR 1.02, 95%CI 1.00 - 1.06, P < 0.01), admission plasma glucose (OR 1.14, 95%CI 1.08 - 1.21, P < 0.01), time from pain to PCI (OR 1.67, 95%CI 0.46 - 5.97, P = 0.012), pre PCI thrombus score ≥ 4 (OR 2.67, 95%CI 1.29 - 5.13, P = 0.008), collateral circulation grade ≤ 1 (OR 1.86, 95%CI 1.27 - 2.73, P = 0.008), and Killip classes (OR 2.01, 95%CI 1.01 - 3.94, P = 0.042) were independent predictors of no-reflow post primary PCI. The plasma level of uric acid on admission is a strong and independent predictor of poor coronary blood flow following at post-primary PCI among STEMI patients. Uric acid levels may be a useful biomarker of risk stratification.

REstoration of COronary flow in patients with no-reflow after primary coronary interVEntion of acute myocaRdial infarction (RECOVER)

No randomized trial has been conducted to compare different vasodilators for treating no-reflow during primary percutaneous coronary intervention (PCI) for ST-segment elevation acute myocardial infarction. The prospective, randomized, 2-center trial was designed to compare the effect of 3 different vasodilators on coronary no-reflow. A total of 102 patients with no-reflow in primary PCI were randomized to receive intracoronary infusion of diltiazem, verapamil, or nitroglycerin (n = 34 in each group) through selective microcatheter. The primary end point was coronary flow improvement in corrected thrombolysis in myocardial infarction frame count (CTFC) after administration of the drug. Compared with that of the nitroglycerin group, there was a significant improvement of CTFC after drug infusion in the diltiazem and verapamil groups (42.4 frames vs 28.1 and 28.4 frames, P < .001). The improvement in CTFC was similar between the diltiazem and verapamil groups (P = .9). Compared with the nitroglycerin group, the diltiazem and verapamil groups had more complete ST-segment resolution at 3 hours after PCI, lower peak troponin T level, and lower N-terminal pro-B-type natriuretic peptide levels at 1 and 30 days after PCI. After drug infusion, the drop of heart rate and systolic blood pressure in the verapamil group was greater than that in the diltiazem and nitroglycerin groups. Intracoronary infusion of diltiazem or verapamil can reverse no-reflow more effectively than nitroglycerin during primary PCI for acute myocardial infarction. The efficacy of diltiazem and verapamil is similar, and diltiazem seems safer.

Effect of Enhanced External Counterpulsation on Coronary Slow Flow and Its Relation with Endothelial Function and Inflammation: A Mid-Term Follow-Up Study

Background: Although enhanced external counterpulsation (EECP) showed short-term effects in improving coronary flow in patients with coronary slow flow (CSF), whether such improvement is durable remains uncertain, and the relationships between such improvement and changes in endothelial function as well as inflammatory markers have not been elucidated. Objectives: The aim of the present study was to investigate the effects of EECP on transthoracic coronary flow, flow-mediated dilatation (FMD), and high-sensitivity C-reactive protein (hsCRP) in patients with CSF. Methods: Forty-five patients with documented CSF underwent transthoracic Doppler echocardiography (TTDE) for the assessment of coronary diastolic peak flow velocity (DPFV) and coronary flow reserve (CFR), and measurements of FMD and hsCRP; they were then nonrandomly assigned to two groups. Subjects in the control group (n = 24) received only medical therapy, and those in the EECP group (n = 21) were additionally treated with the 36 one-hour sessions of EECP. After 8 weeks of medical/EECP therapy, TTDE, FMD, and hsCRP examinations were repeated, and TTDE was additionally repeated after the 6-month clinical follow-up. Results: In the EECP group, resting DPFV, hyperemic DPFV, and CFR were significantly increased shortly after therapy (p < 0.001) and the improvement was maintained up to the 6-month follow-up, whereas in the control group those variables were not statistically increased. Meanwhile, hsCRP significantly decreased and FMD increased after therapy in the EECP group (p < 0.001). In all subjects, CFR improvement was negatively correlated with hsCRP change and positively correlated with FMD increase (p < 0.001). Conclusions: EECP may have a durable effect in improving coronary flow in patients with CSF. Such improvement is related to the favorable effects of EECP on vascular inflammation and endothelial function.

Reducing door-to-balloon time for STEMI—success at a price

To achieve timely restoration of coronary flow in patients with acute myocardial infarction, the decision to call in the cardiac catheterization team has moved ever earlier, and is often made before cardiologist evaluation. Door-to-balloon times have been reduced, but the price of this success is an increase in 'false alarms'.

Slow coronary flow in patients undergoing urgent coronary angiography for ST elevation myocardial infarction

First, we would like to thank Pr Neil Langlois for his kind comment [1] and his interest about our manuscript and its related photomicroscopy images. We clearly considered his opinion and realized new analyses which were against the diagnosis of Mesothelial Incidental Excrescence (MICE). Indeedmesothelial markers were found negative (CD 15 and calretitin), as well as the third marker CK 7(and the only one tested at the time the case was reported). As far as we know, we still believe we reported with this manuscript [2] the first case of a cancer hang on a pacemaker lead. Again, we did appreciate the comment and were delighted to test other mesothelial markers to fully answer this interesting question. none. The authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology (Shewan and Coats 2010; 144:1–2).

Cardiopulmonary exercise testing for the assessment of exercise capacity in patients with cardiac syndrome X

after EECP therapy. The improvement in coronary blood flow is consistent with angina relief. The correlations between CFVmeasured by TTDE and angiographic TFC have not been fully elucidated in patients with CSF. Our present study demonstrated that there was an excellent inverse correlation between resting DPFV and TFC for LAD, and CFR was inversely correlated with mean TFC, which are consistent with the results reported by Caliskan et al. [5]. These results suggested that CFV and CFR measured by TTDE could be reliable indices for assessing patients with CSF. The mechanisms responsible for improving coronary blood flow of EECP are unclear. As an effective noninvasive treatment method for patients with coronary artery disease, EECP has been proved to exert various beneficial effects on cardiovascular system, such as increasing coronary perfusion pressure and the arterial wall shear stress, improving endothelial function, decreasing inflammation, promoting vascular remodeling, triggering angiogenesis, improving microvascular dysfunction, and ameliorating blood rheology [6]. All these effects may help to improve coronary flow in patients with CSF. We should acknowledge some limitations of this study. It is not a randomized and sham-controlled study for practical reasons, although the baseline data between groups were comparable. The second limitation is the lack of repeat angiographic measurements after therapy. In addition, long-term follow-up studies powered on clinical outcomes are warranted to confirm the efficacy of EECP for treatment of CSF. In conclusion, EECP is effective for improving coronary flow velocity and coronary flow reserve in patients with coronary slow flow. EECP may be considered an effective new therapeutic modality in the management of coronary slow flow, and larger randomized and sham-controlled clinical studies arewarranted to confirm the findings of this study.

The association of serum uric acid levels on coronary flow in patients with STEMI undergoing primary PCI

ObjectiveUric acid has been shown as a predictor and an independent risk factor for coronary heart disease, but little is known regarding the association of uric acid levels with coronary blood flow in STEMI. We hypothesized that elevated uric acid levels would be associated with impaired flow and perfusion in the setting of STEMI treated with primary PCI. MethodsTwo hundred and eighty nine patients with STEMI who treated primary PCI were enrolled to study. Patients were divided into two groups based upon the TIMI flow grade. No-reflow was defined as TIMI Grade 0, 1 and 2 flows (group 1). Angiographic success was defined as TIMI 3 flow (group 2). Uric acid, MPV and high sensitive CRP were measured. Major adverse cardiac events (MACE) were defined as in stent thrombosis, non-fatal myocardial infarction and in-hospital mortality. ResultsThere were 126 patients (mean age 63±11 and 71% male) in group 1 and 163 patients (mean age 58±12 and 80% male) in group 2. Uric acid, MPV, and hs-CRP levels on admission were higher in group 1 (p=0.0001 for each). A uric acid level ≥5.4mg/dl measured on admission had a 77% sensitivity and 70% specificity in predicting no-reflow at ROC curve analysis. In-hospital MACE was significantly higher in group 1 (29% vs. 7%, p=0.0001). At multivariate analyses, high plasma uric acid (odds ratio (OR) 2.05, <95% confidence interval(CI) 1.49–2.81; p<0.0001), hs-CRP (OR 1.02, <95% CI 1.01–1.03; p=0.0007) and MPV (OR 3.09, <95% CI 1.95–4.89; p<0.0001) levels were independent predictors of no-reflow post primary PCI and uric acid (OR 2.75, <95% CI 1.93–3.94; p<0.0001), hs-CRP (OR 1.01, <95% CI 1–1.02; p=0.006) levels, but not MPV, were independent predictors of in-hospital MACE. ConclusionPlasma uric acid level on admission is a strong and independent predictor of poor coronary blood flow following primary PCI and in hospital MACE among patients with STEMI. Except for predictive value, uric acid levels may be a useful biomarker for stratification of risk in patients with STEMI and may also lead to carry further therapeutic implications.

Prediction of Myocardial Functional Recovery by Noninvasive Evaluation of Basal and Hyperemic Coronary Flow in Patients with Previous Myocardial Infarction

The aim of this study was to evaluate the relation of basal and hyperemic coronary flow with myocardial functional improvement in patients with previous myocardial infarction undergoing elective percutaneous coronary intervention (PCI). Coronary flow was measured using transthoracic Doppler echocardiography in 50 patients (41 men; mean age, 53 ± 8 years) with previous myocardial infarction before, 24 hours, and 3 months after elective PCI. Diastolic deceleration time (DDT) was measured from the peak diastolic velocity to the point of intercept of initial decay slope with baseline. Coronary flow reserve (CFR) was calculated as the ratio of hyperemic to basal peak diastolic flow velocities. In comparison with patients without improvements in left ventricular function, patients with recovered left ventricular function had longer DDTs before angioplasty (841 ± 286 vs. 435 ± 80 msec, P < .001). CFR was significantly higher in recovered compared with nonrecovered patients (2.60 ± 0.70 vs. 2.16 ± 0.34, P = .034) 24 hours after PCI. Global and regional wall motion scores before PCI, end-diastolic and end-systolic volumes, and CFR 24 hours after PCI and DDT before PCI were univariate predictors of left ventricular functional recovery. By multivariate analysis, DDT and regional wall motion score before PCI were independent predictors of left ventricular recovery in the follow-up period (P = .003 and P = .007, respectively). In patients with previous myocardial infarction undergoing elective PCI, evaluation of basal coronary flow pattern and measurement of DDT before angioplasty may predict functional improvement of myocardium in the follow-up period and could be useful quantitative parameters in the evaluation of potential improvement in myocardial function.

Coronary Flow in Patients with Three-Vessel Disease: Simulated Hemodynamic Variables in relation to Angiographically Assessed Collaterality and History of Myocardial Infarction

We study patients with stenoses of the left main coronary artery (LMCA), left anterior descending artery (LAD), and left circumflex branch (LCx) and with chronic occlusion of the right coronary artery (RCA), undergoing off-pump coronary surgery. An analog electrical model is used to provide quantitative estimations of the distribution of flows and pressures across the coronary network (in the stenosed native arteries, the collateral branches, the capillary areas, and so forth). The present paper demonstrates that the clinical information collected for the 10 patients included in the study (Rentrop score, history of myocardial infarction, left ventricular ejection fraction (LVEF)) are well correlated with the predicted hydrodynamic data. Patients with a good collaterality (Rentrop score = 3) or patients without anterior myocardial infarction have (i) less severe stenoses on the LMCA, (ii) lower microvascular resistances, (iii) higher grafts flow rates when the revascularization is performed, (iv) higher collateral flow rates towards the territory of the occluded artery, (v) better perfusion of this area, and (vi) better total perfusion of the heart.

Microvascular Thrombosis: An Exciting but Elusive Therapeutic Target in Reperfused Acute Myocardial Infarction

The beneficial effects of restoration of coronary flow in patients with acute myocardial infarction may be hampered by inadequate tissue perfusion. Among other factors, it is likely that platelets contribute substantially to this phenomenon. Platelets may compromise blood flow at the microvascular level by forming a part of microemboli, by adhering to reperfused, capillary or venular endothelium or to attached leukocytes, by releasing substances producing vasoconstriction, or through toxic effects. Patients with acute coronary syndromes have an increased number of circulating activated platelets, and this systemic platelet activation has been related to the presence and extent of myocardial necrosis. The mechanisms of platelet deposition to reperfused microvessels are not fully understood, but likely involve the interaction between adhesion molecules such as selectins or glycoproteins expressed on these cells upon activation and their ligands on the surface of endothelial cells or polymorphonuclear leukocytes. While these interactions are potentially important therapeutic targets in acute myocardial infarction, reducing platelet deposition and increasing myocardial salvage by direct effects on the microvasculature is still challenging with the existing armamentarium of antiplatelet agents. This review summarizes the current knowledge on the mechanisms of platelet-mediated myocardial damage after reperfusion and the effects of pharmacological interventions aimed to reduce microvascular platelet deposition and platelet-mediated myocardial injury.

The effect of verapamil and nitroglycerin on the coronary slow flow phenomenon

Objective: The aim of this study was to assess the effect of nitroglycerin and verapamil on the coronary flow in patients with the coronary slow flow (CSF) phenomenon (CSFP). Design and methods: Sixty-four patients with CSF and no stenotic lesions during diagnostic coronary angiography were enrolled and divided into the nitroglycerin group (n=35) and verapamil group (n=29), and 29 patients with normal coronary flow were selected as normal. CSFP was defined as it required 4 or more beats for the contrast media to opacify the distal vasculature. Intracoronary injection of 100–400 μg nitroglycerin or verapamil was not given in patients with CSFP until the coronary flow improved. The coronary blood flow was evaluated by Thrombolysis in Myocardial Infarction frame count (TFC) method in this study. Results: There was no difference regarding the clinical characteristics among the three groups. The basic TFCs of the left anterior descending artery (LAD), left circumflex artery (LCX) and right coronary artery (RCA) were 78.28±19.40, 57.24±14.58, and 56.87±12.47 in the verapamil group, and were 70.84±21.66, 55.33±12.52, and 51.05± 15.35 in the nitroglycerin group, respectively, which were significantly higher than those in the normal controls (LAD 29.15±4.42, LCX 23.14± 3.48 and RCA 19.72±1.75, respectively). After the administration of drugs, the TFCs of LAD, LCX and RCA were 42.32±8.88, 36.65±6.78, and 30.32±5.94, respectively (vs. base, all P<0.05) in nitroglycerin group and 37.68±9.31, 31.50±11.30, and 24.58±4.40 respectively (vs. base, all P<0.05) in the verapamil group. The TFCs in both the two groups after the administration of drugs were still higher than that in normal controls (all P<0.05). The TFCs in the verapamil group had a larger decrease than those in the nitroglycerin group (P<0.05). Conclusions: Intracoronary administration of verapamil could result in more improvement of the coronary flow in patients with CSFP than after the administration of nitroglycerin, although the coronary flow was still slower than normal.