Enhanced myocardial washout and retrograde blood delivery with synchronized retroperfusion during acute myocardial ischemia

The effects of synchronized coronary venous retroperfusion of arterial blood on myocardial washout were studied with digital subtraction angiography in 10 closed chest dogs during balloon occlusion of the proximal left anterior descending coronary artery. The center lumen of the intracoronary balloon catheter was used for sequential injections of 1 ml (meglumine diatrizoate) Renografin-76, and contrast washout rate was determined by videodensitometry in myocardial regions subserved by the left anterior descending coronary artery. Before coronary artery occlusion, washout rate was 22.4 +/- 2.7 min-1 (mean +/- SEM). Five minutes after occlusion, and immediately before synchronized retroperfusion, washout rate dropped sharply to 2.0 +/- 0.7 min-1. Twenty-five minutes after occlusion, with 50 ml/min synchronized retroperfusion treatment applied for 5 minutes, washout rate was 5.0 +/- 1.5 min-1. Thus, synchronized retroperfusion significantly (p less than 0.05) accelerated contrast disappearance over that during presynchronized retroperfusion ischemia. To determine the effects of synchronized retroperfusion on retrograde delivery to the ischemic myocardium, monastral blue dye was retroinfused through the system into the great cardiac vein before the dog was killed. Transverse heart slices were then studied by light microscopy, and regional intravascular dye content was scored from 0 to 3 (0 = no dye, 3 = maximal dye). After great cardiac vein synchronized retroperfusion, blue dye content in capillaries of ischemic anterior and nonischemic posterior aspects of the left ventricle was 2.3 +/- 0.5 versus 0.7 +/- 0.3, respectively (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Combined intraaortic balloon counterpulsation with synchronized coronary venous retroperfusion: The united states experience

Prompted by severe cardiogenic shock, impending or manifest, three cases from the United States Retroperfusion Clinical Trials utilized intraaortic balloon counterpulsation combined with retroperfusion. Temporary stabilization and improvement was noted in all three cases and long-term survival was seen in two of the cases. The clinical and physiologic bases for combined use of these modalities is discussed. © Wiley-Liss, Inc.     

Coronary venous retroperfusion delivery of treatment to ischemic myocardium

Renewed efforts are under way to apply clinically oriented coronary venous retroperfusion methods for treatment of myocardium jeopardized by major coronary artery obstructions. Based upon improved understanding of criteria for retroperfusion effectiveness and safety, improved arterial blood retroperfusion and pharmacologic agent retroinfusion techniques have been demonstrated to provide significant myocardial infarct salvage and enhance cardiac function. The retrograde systems also have a potential for prompt lysis of an acute coronary artery thrombus and for treatment of refractory arrhythmias. Retroperfusion may constitute an effective protective support when used in conjunction with new aggressive interventions, maintaining jeopardized myocardial viability and function pending permanent reversal of a severe coronary flow insufficiency or emergency revascularization in evolving acute infarction. Clinical applications are anticipated in the setting of unstable angina and arrhythmias, as circulatory assist during complex coronary angioplasty and thrombolytic procedures, and as adjunct support of cardiac surgery.     

Coronary venous blood flow in patients with acute myocardial infarction

In 94 patients with large myocardial infarction, their coronary venous blood flow was studied in the acute period of the disease by continuous coronary sinus thermodilution. No relationship was established between the coronary venous blood flow and the duration of coronary heart disease. The patients with anterior myocardial infarction had a significantly less blood flow in the vena cordis magna than those with posterolateral infarction. No correlation was found between the blood flow and precordial mapping parameters. Thus, continuous coronary sinus thermodilution cannot be used for indirect identification of the site of myocardial infarction and for prediction of its progression severity.     

Coagulation of arterial and venous blood in acute myocardial infarct]

The conducted study has demonstrated that aged patients with large focal and transmural myocardial infarctions had coagulation changes throughout the acute period of the disease that manifested themselves predominantly in the arterial bed and displayed clear phase-wise fluctuations. The coagulability of peripheral venous blood failed to give a distinct picture of the true state of blood coagulation.     

Coronary artery stenting for acute closure complicating primary angioplasty for acute myocardial infarction

We report a case of progressive right coronary artery dissection complicating direct angioplasty for an acute inferior myocardial infarct, with successful bail-out stenting of the affected vessel.     

Coronary sinus reducer implantation in the middle cardiac vein for the treatment of refractory angina

Coronary sinus Reducer is a current therapeutic treatment for patients with persistent refractory angina. We report a case of successful implantation of the device in the middle cardiac vein of a 65 years old female patient. The singular and unusual site for the Reducer was planned after a careful assessment of the venous drainage of the ischemic territory.     

Arterial blood infusion for myocardial protection during percutaneous transluminal coronary angioplasty

Much of the potential risk of percutaneous transluminal coronaryangioplasty relates to regional myocardial ischaemia duringballoon inflation. We have investigated the protective effectof infusing arterial blood through the angioplasty catheterinto the distal coronary artery during 60 second balloon inflations.Symptomatic, electrocardiographic and echocardiographic indicesof regional ischaemia were monitored during inflations withand without blood infusion. The effect of infusing Hartmann'ssolution was also evaluated to control for washout effects.Twelve patients were studied. Inflation without blood producedchest pain in eight patients, ST-segment elevation in ten patientsand regional wall motion abnormalities in every case. Duringblood infusion manifestations of ischaemia were either delayedor prevented altogether. Chest pain occurred in only one patientwhile ST segment elevation and regional wall motion abnormalitiesoccurred in three and four patients, respectively. Infusionof Hartmann's solution, on the other hand, had no significanteffect on the development of regional myocardial ischaemia duringballoon inflation indicating that delivery of arterial oxygenand not washout of metabolites was responsible for the beneficialeffects of blood infusion. These data indicate that distal coronaryperfusion with arterial blood during angioplasty reduces regionalmyocardial ischaemia and has the potential to improve the safetyof the technique and to permit more prolonged periods of ballooninflation.     

Severe transmural myocardial ischemia after dipyridamole administration implicating coronary steal

Myocardial perfusion imaging with coronary vasodilators is routinely used for patients with suspected coronary disease who are unable to exercise. Since these agents work by increasing blood flow without significantly changing myocardial oxygen demand, they generally do not produce ischemia. A minority of patients show evidence of ischemia which some investigators suggest is due to a coronary steal phenomenon, but this has been challenged by several investigators. We present the case of a patient who developed severe transmural myocardial ischemia manifested by ST-segment elevation and severe perfusion defects which occurred after dipyridamole administration and which were reversed with aminophylline and nitroglycerin. This case supports the notion that coronary vasodilation with dipyridamole can induce a coronary steal.     

Effects of diastolic synchronized retroperfusion on regional coronary blood flow in experimental myocardial ischemia

Coronary venous retroperfusion has previously been suggested as a potential mode of treatment of myocardial ischemia. This study was designed to examine the actual changes in regional myocardial blood flow that occur with diastolic synchronized retroperfusion of the coronary sinus. Coronary sinus retroperfusion consisted of (1) diastolic augmentation of delivery of arterial blood into the acutely ischemic myocardium, and (2) systolic facilitation of coronary venous drainage. This was achieved using a gas-actuated electrocardiogram-synchronized retroperfusion pump that propels arterial blood during diastole through an autoinflatable bladder catheter. Hemodynamic data and measurements of ischemic tissue injury (S-T segment mapping) and regional myocardial blood flow (radioactive microsphere technique) were obtained before and after 1 and 2 hours of coronary arterial occlusion. Experiments were performed in 19 open chest dogs: Retroperfusion was instituted after the 1st hour of coronary occlusion and maintained for the subsequent hour in 8 dogs and the results were compared with those obtained in 6 randomly selected untreated dogs. In five additional dogs, the fraction of microspheres escaping myocardial entrapment in either an anterograde or a retrograde direction was determined. In both treated and untreated dogs, changes in hemodynamics, S-T segment mapping and regional myocardial blood flow showed the same trend up to 1 hour of coronary occlusion. Synchronized retroperfusion resulted in a minor but significant decrease in heart rate and an increase in stroke volume. As early as 15 minutes after the start of synchronized retroperfusion, there was a significant decrease in S-T segment elevation (from 5.95 ± 1.01 to 3.09 ± 0.58 mV [mean ± standard error of the mean], p <0.01) that was maintained for the subsequent hour; in the control series, S-T segment elevation was unaffected. After 1 hour of retroperfusion, regional transmural flow increased in the nonischemic zone from 0.84 ± 0.07 to 1.05 ± 0.10 ml/min per g (p <0.05) with an unchanged $\text{endocardial}\text{epicardial}$ flow ratio (1.10 ± 0.04 and 1.11 ± 0.04 before and 1 hour after treatment, respectively). In the ischemic zone, 1 hour of retroperfusion increased transmural flow by 59.3 percent (from 0.32 ± 0.05 to 0.51 ± 0.04 ml/min per g, p <0.05) with a greater increase in endocardial flow (from 0.19 ± 0.02 to 0.35 ± 0.03 ml/min per g, p <0.05) than in epicardial flow (from 0.43 ± 0.05 to 0.59 ± 0.06 ml/min per g, p <0.01) leading to a significant increase in $\text{endocardial}\text{epicardial}$ flow ratio (from 0.46 ± 0.05 to 0.64 ± 0.07, p <0.01).These experimental data show that retroperfused arterial blood reaches the ischemic as well as the nonischemic zones and is favorably redistributed toward the endocardium. Thus, diastolic synchronized retroperfusion is capable of restoring nutritional blood flow to approximately 50 percent of normal control flow. This improvement in myocardial perfusion might be of value in delaying irreversible myocardial ischemia.     

Coronary stenting for failed angioplasty in acute myocardial infarction

Intracoronary stents were implanted in 15 patients after unsuccessful PTCA in the setting of acute myocardial infarction (AMI). The stented vessel was the left anterior descending (LAD) in 11 patients, the right coronary artery (RCA) in 3 patients, and a venous bypass graft to the LAD in a single patient. A total of 16 stents were implanted (15 Palmaz-Schatz, Johnson and Johnson; and 1 Wiktor, Medtronic). Follow-up: 1 patient died 10 days after stent implantation as a result of renal failure and cardiogenic shock. Subacute thrombosis occurred in 2 patients, 5 and 15 days after stent implantation; both underwent successful emergency coronary artery bypass grafting (CABG). The remaining 12 patients were free from major ischemic events (death, AMI, and further revascularization) after a mean follow-up of 18.7 ± 4.1 months. We conclude that the long-term results of intracoronary stenting in AMI after failed PTCA are favourable. © 1996 Wiley-Liss, Inc.     

Coronary revascularization for acute myocardial infarction in the HIV population

Objective

To analyze trends in management and outcomes of patients infected with the human immunodeficiency virus (HIV) undergoing percutaneous coronary intervention (PCI) for an acute myocardial infarction (AMI) in the United States.

Background

Infection with HIV is an independent risk factor for accelerated atherosclerosis associated with higher rates of AMI. Current trends and outcomes of HIV‐infected individuals presenting with AMI in the United States remain unknown.

Methods

Using the Healthcare Cost and Utilization Project National Inpatient Sample database we identified HIV‐infected individuals who underwent PCI for an AMI from 2002 to 2013. Multivariable logistic regression and propensity‐score matching were performed to analyze outcomes.

Results

We identified a total of 59 194 patients of which 7841 underwent PCI during index hospitalization (13.3%). Most patients were men (71%), ≥50 years of age (82%), and white (74%). ST‐elevation myocardial infarction was present in 21% of cases. Charlson comorbidity index (CCI) was 5.67 ± 0.4. Predictors of post‐procedural complications included female sex, black race, higher CCI, and placement of a bare metal stent, whereas predictors of mortality included occurrence of a complication, ST‐elevation myocardial infarction, age ≥70 years, and higher CCI. Conversely, placement of a drug‐eluting stent was associated with a reduced risk of complications and mortality. After propensity‐score matching, HIV‐infected individuals were less likely to undergo PCI and receive a drug‐eluting stent, while having longer length of stay, higher hospitalization costs, and higher in‐hospital mortality when compared to non‐infected individuals.

Conclusion

Significant disparities continue to affect HIV‐infected individuals undergoing PCI for AMI in the United States.

     

Effect of myocardial ischemia on prostacyclin and thromboxane levels in arterial and coronary venous blood

Variations in arterial and venous blood prostacyclin and thromboxane were examined in 32 patients with coronary heart disease, neurocirculatory dystonia and the cardialgic syndrome, exposed to cardioselective stress as a result of the atrial stimulation test. Prostacyclin and thromboxane measurement in blood specimens obtained from the left ventricle and the coronary venous network may provide additional markers of myocardial ischemia in cases where diagnosis is otherwise difficult to make.     

Ethanol-induced myocardial ischemia: Close relation between blood acetaldehyde level and myocardial ischemia

A patient with vasospastic angina who developed myocardial ischemia following ethanol ingestion but not after exercise was described. Myocardial ischemia was evidenced by electrocardiograms (ECGs) and thallium-201 scintigrams. The blood acetaldehyde level after ethanol ingestion was abnormally high. The time course and severity of myocardial ischemia coincided with those of the blood ethanol and acetaldehyde level. Coronary arteriography showed ergonovine maleate-induced coronary vasospasm at the left anterior descending coronary artery. ECG changes similar to those induced by ethanol ingestion were observed at the same time. These findings suggest that the high blood acetaldehyde level might be responsible for the development of coronary vasospasm and myocardial ischemia in this patient.     

冠状动脉慢血流与心肌缺血的关系

目的:通过腺苷负荷心肌灌注显像(SPECT),评价冠状动脉慢血流现象(CSF)与心肌缺血的关系。方法:选择经冠状动脉造影(CAG)诊断为CSF者20例,CAG显示无管腔狭窄及无慢血流者20例为对照组。使用校正的TIMI血流分级(CTFC)方法评价冠状动脉血流速度,2组均行心电图及腺苷负荷SPECT检查。结果:CSF者发生心电图及腺苷负荷SPECT异常的例数比对照组明显增多,同时心肌缺血的范围与缺血程度也均大于血流正常者(P<0.01)。结论:腺苷负荷SPECT发现CSF存在可逆性心肌缺血,可能CSF与心肌缺血关系密切。