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C L Grines

Publications and source records attributed to C L Grines.

119 records · Page 7Linked to original sources
PubMed1989

Prognostic implications and predictors of enhanced regional wall motion of the noninfarct zone after thrombolysis and angioplasty therapy of acute myocardial infarction. The TAMI Study Groups.

Although impairment of left ventricular function in acute myocardial infarction is closely related to extent of necrosis, function in the noninfarct zone also contributes to global performance and thus may be of prognostic importance. We evaluated left ventricular regional wall motion by the centerline chord method in 332 patients treated with intravenous tissue-type plasminogen activator (t-PA) in the multicenter Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) I trial. All patients had acute contrast ventriculograms of suitable quality for analysis, and 266 patients had paired acute and day 7 ventriculograms. Enhanced function of the noninfarct zone was present during acute catheterization (+0.3 SD/chord) and was associated with preservation of the acute ejection fraction (p = 0.0001). Multiple linear regression analysis revealed the most powerful clinical factor associated with enhanced function of the noninfarct zone was the absence of multivessel disease (p = 0.0001). Clinical factors that were related weakly to noninfarct zone function included female gender (p = 0.08) and higher flow in the infarct artery (p = 0.03). Neither the degree of infarct zone dysfunction nor infarct location was associated with hyperkinesis of the noninfarct zone. In hospital, mortality was closely related to function in the noninfarct zone (p = 0.006), ejection fraction (p = 0.025), and the number of diseased vessels (p = 0.009) but was not related to infarct zone function (p = 0.128).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1988

Comparison of left ventricular function and contractile reserve after successful recanalization by thrombolysis versus rescue percutaneous transluminal coronary angioplasty for acute myocardial infarction.

To determine how coronary reperfusion affects rest and exercise ventricular function after acute myocardial infarction (AMI), 63 patients with a patent infarct artery after intravenous thrombolytic therapy (lysis) were compared with 27 patients who failed thrombolysis but had successful acute recanalization by percutaneous transluminal coronary angioplasty (PTCA) as a "rescue" procedure. Contrast ventriculography was performed acutely and on day 7. Resting radionuclide ventriculography was performed at 24 hours and repeated with exercise on day 30. There were no differences in global ejection fraction (EF) between the 2 groups during acute contrast ventriculography. However, by 24 hours, the EF had deteriorated in the rescue group (40 +/- 17 vs 49 +/- 11% in the lysis group, p less than or equal to 0.05). No improvement occurred in either group on day 7. By day 30, an improvement in resting radionuclide EF 5.9 +/- 1.9% occurred in rescue patients and the difference between rescue and lysis groups was no longer significant (46 +/- 14 vs 50 +/- 11%, p = 0.12). A normal (greater than or equal to 5%) increase in EF with exercise occurred in 64%, with either normal or exercise-enhanced regional wall motion present in 67% of patients. A significant increase in EF occurred within the rescue group, from 46 +/- 14% at rest to 50 +/- 15% at peak exercise (p less than or equal to 0.0005). The EF increased with exercise from 50 +/- 11 to 58 +/- 15% in the lysis group (p less than or equal to 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1988

Infarct vessel status after intravenous tissue plasminogen activator and acute coronary angioplasty: prediction of clinical outcome.

To determine the risk of arterial reocclusion or recurrent ischemia after acute intervention in myocardial infarction, we analyzed the results of coronary arteriography performed acutely and at 1 week in 50 consecutive patients who received acute intervention. Successful recanalization of the infarct vessel was achieved in 46 (92%) patients after therapy with intravenous tissue plasminogen activator, percutaneous coronary angioplasty, or both. Follow-up angiography in 44 showed early reocclusion in 10 patients (23%). Intermittent patency during acute arteriography was always associated with reocclusion; suboptimal (Thrombolysis in Myocardial Infarction [TIMI] class 2) flow was associated with a 50% rate of reocclusion. Although residual stenosis of greater than 50% alone was not predictive of rethrombosis, 90% of all reocclusions were associated with either stenosis greater than 50%, TIMI 2 flow, or intermittent patency. Absence of these angiographic risk factors predicted a 95% patency rate at follow-up. In-hospital cardiac complications occurred in 17 of 23 (74%) patients with residual stenosis of greater than 50% (death in four, ischemia in 13), and late revascularization was required in 53% of survivors. Only 15% of the group with less than 50% stenosis had an in-hospital ischemic event (p less than 0.001). Thus, after acute intervention, an infarct vessel with intermittent patency or suboptimal flow is associated with a high rate of reocclusion. Residual stenosis greater than or equal to 50% appears to predict a high incidence of negative in-hospital clinical outcomes and the need for subsequent revascularization.

Adult↗
PubMed1988

Postural exercise abnormalities in symptomatic patients with mitral valve prolapse.

The hemodynamics of the supine and upright exercise response in 16 symptomatic women with mitral valve prolapse (Group I) was compared with that in 8 asymptomatic normal control women (Group II). All subjects had supine and upright echocardiography and phonocardiography at rest and none demonstrated mitral regurgitation. All participants then underwent same day graded bicycle exercise, with simultaneous radionuclide angiography in both the upright and the supine posture. Catecholamines were measured, and a variety of volumetric and hemodynamic data were obtained. Group I (patients with mitral valve prolapse) demonstrated a reduced exercise tolerance, especially during upright exercise, as measured by both total exercise duration and maximal work load achieved. Mean total catecholamine measurements were similar between the two study groups at comparable mean heart rate, mean blood pressure and mean rate-pressure (double) product. No difference was observed in the ratio of right to left ventricular stroke counts at rest or during exercise regardless of posture, suggesting that exercise-induced mitral regurgitation did not occur. A difference was noted, however, in left ventricular end-diastolic volume index. At rest, Group I patients exhibited a 42% decrease in this index when sitting upright, and this difference from supine values persisted at submaximal (300 kpm/min) and peak work loads (34 and 29% difference, respectively). This contrasted with the control subjects whose upright end-diastolic volumes at rest, at 300 kpm/min and at peak exercise were reduced 21, 10 and 3%, respectively, compared with supine values. Cardiac index measurements reflected the reduced left ventricular end-diastolic volume observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Predictors of success for coronary angioplasty performed for acute myocardial infarction.

To evaluate the predictors and likelihood of success for coronary angioplasty performed in the setting of acute myocardial infarction, 300 consecutive patients with 321 coronary stenoses were studied retrospectively. Success was defined as final diameter stenosis less than 70% and Thrombolysis in Myocardial Infarction (TIMI) flow grade greater than or equal to 2. Nine clinical variables and 15 angiographic variables were assessed. Seventy-nine percent of patients were men; the mean age was 56 +/- 11 years, and 54% of patients also received thrombolytic therapy. The mean left ventricular ejection fraction was 46 +/- 11%, and 18 patients (6%) were in cardiogenic shock. Angioplasty success in the infarct-related artery was achieved in 240 patients (80%). In 177 total occlusions (TIMI flow grade less than or equal to 1), the success rate was 75.7% and success was independently predicted by 1) an ejection fraction greater than 30% (p = 0.001); 2) no arterial bend greater than or equal to 45 degrees at the site of angioplasty (p = 0.008); and 3) no triple vessel disease (p = 0.014). In 144 subtotal occlusions (TIMI flow grade greater than or equal to 2), procedural success was achieved in 84.7% and was predicted by 1) absence of thrombus greater than 5 mm (p = 0.023), and 2) absence of other stenoses greater than or equal to 50% in the same artery (p = 0.043), whereas patency without further emergency intervention was achieved in 71.7% and was predicted only by patient age less than or equal to 60 years and absence of cardiogenic shock.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1987

A randomized, placebo-controlled trial of intravenous recombinant tissue-type plasminogen activator and emergency coronary angioplasty in patients with acute myocardial infarction.

To determine the role of tissue-type plasminogen activator (t-PA) and immediate percutaneous transluminal coronary angioplasty (PTCA) in treating patients with evolving transmural myocardial infarction, 50 patients received t-PA (1.25 mg/kg iv over 3 hrs) or placebo according to 3:1 double-blind randomization 3.8 +/- 1.1 hr after onset of symptoms. At emergency coronary arteriography, patency of the infarct-related vessel was demonstrated in 32 of 38 (84%) patients receiving t-PA vs two of 12 (17%) receiving placebo (p less than .001). Of the 32 patients with recanalization after t-PA, 28 had a residual stenosis of at least 50% and underwent randomization a second time to immediate (n = 15) or no PTCA (n = 13). Immediate PTCA of the infarct-related vessel was successful in all 15 patients, with reduction of the residual diameter stenosis from 80.8 +/- 8.2% to 32.5 +/- 15.6% (p less than .001). The incidence of postinfarction angina (greater than or equal to 20 min of chest discomfort and reversible electrocardiographic changes) and reinfarction (documented by recurrent creatine kinase isoenzyme elevation) was reduced in the patients receiving t-PA and PTCA (2/15) compared with that in patients receiving t-PA alone (7/13; p = .006). At 1 week there was no difference in patency of the infarct-related vessel (12/15 t-PA and PTCA vs 9/13 t-PA only) or in global ventricular functional change between the two groups (0.5 +/- 10.4 SD/chord for t-PA and PTCA vs -2.1 +/- 8.2 SD/chord for t-PA only).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1987

Measurement of regional myocardial perfusion and mass by subselective hydrogen infusion and washout techniques: a validation study.

A technique was developed for measuring regional myocardial perfusion by intracoronary infusions of hydrogen (H2)-saturated saline. H2 concentration was detected during washout in the pulmonary artery by means of the voltage response of a platinum-tipped electrode. Regional myocardial perfusion was calculated from the H2 exponential desaturation curve according to the Kety-Schmidt principle. In 16 anesthetized open-chest dogs, validation of this technique was performed at baseline, reduced (stenosis), and hyperemic (dipyridamole) flow states by means of the radionuclide-labeled microsphere reference withdrawal technique. There was an excellent quadratic correlation between microsphere and H2 washout techniques (range 0.11 to 3.15 ml/min/g) (n = 33, r = .92, y = -0.12x2 + 0.89x + 0.20, SEE = 0.20 ml/min/g; p less than .0001). Hyperemic regional myocardial perfusion was underestimated by H2 washout and severely ischemic regional myocardial perfusion was overestimated. When regional myocardial perfusion values greater than twice normal were excluded, a strong linear correlation was present between H2 and microsphere measurements (n = 27, r = .89, y = 0.76x + 0.22, SEE = 0.18 ml/min/g; p less than .0001). The H2 washout method was further tested in 18 additional open chest dogs for calculations of the mass of an arterial perfusion bed according to the principle that the mass of the bed (g) equals coronary blood flow (ml/min) divided by regional myocardial perfusion (ml/min/g).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Should every patient undergo cardiac catheterization after myocardial infarction?

During the past few decades, management of patients with myocardial infarction has dramatically evolved. High-risk patients are now identified by a variety of noninvasive tests, and aggressive use of reperfusion strategies has improved clinical outcomes. Despite the benefits of reperfusion, only a few patients are eligible to receive thrombolytic therapy. Mortality rates among patients excluded from thrombolytic trials (15% to 20%) have been far greater than those eligible for treatment (3% to 10%). Because most deaths occur within the first few days of infarction, interventions designed to reduce mortality should be performed acutely. Immediate catheterization allows identification of high-risk anatomy that may benefit from surgery and allows coronary angioplasty to be performed as a reperfusion strategy (when appropriate). Furthermore, catheterization allows documentation of ejection fraction, vessel patency, number of diseased vessels, and residual stenosis, all of which have been predictive of prognosis. Conversely, frequently repeated noninvasive diagnostic tests are associated with increased cost, are generally performed in low-risk patients, and 60% to 80% of patients with myocardial infarction ultimately require catheterization anyway. It is possible that early catheterization and percutaneous transluminal coronary angioplasty when indicated may effectively risk stratify patients (eliminating the need for noninvasive testing), may reduce morbidity and mortality, and shorten the length of hospital stay.

Cardiac Catheterization↗
PubMedDate not supplied

Factors influencing myocardial salvage with primary angioplasty.

BACKGROUND: The purpose of this study was to evaluate the factors influencing the salvage of jeopardized myocardium in patients treated with primary angioplasty for acute myocardial infarction. METHODS AND RESULTS: This multicenter study involved 59 patients with acute myocardial infarction who underwent primary angioplasty without antecedent thrombolytic therapy and paired baseline (before angioplasty) and predischarge tomographic perfusion imaging by quantitative 99mTc-labeled sestamibi techniques for assessing the initial area at risk and eventual infarct size. Of the 59 patients who underwent primary angioplasty, Thrombolysis In Myocardial Infarction (TIMI) level 3 perfusion was restored in the infarct vessel in 54 patients (92%). On average, approximately one third of the left ventricular myocardial mass was initially jeopardized by the infarction in progress; eventual infarct size was 18% +/- 15% of the left ventricle; myocardial salvage was 16% +/- 17% of the left ventricle. Primary angioplasty salvaged 46% +/- 50% of initially jeopardized myocardium. Factors correlated with myocardial salvage included elapsed time from onset of pain to reperfusion, infarct location (anterior infarcts had more myocardial salvage than inferior infarcts), and residual flow to the infarct zone at preangioplasty baseline levels. In the five patients reperfused less than 2 hours from onset of pain, 80% of the jeopardized myocardium was salvaged. Myocardial salvage beyond 2 hours was much more variable. CONCLUSIONS: Primary angioplasty was highly effective at restoring normal perfusion in the infarct vessel and salvaging jeopardized myocardium. The myocardial salvage was highly variable and correlated with elapsed time to reperfusion, baseline residual flow to the infarct zone, and infarct location.

Adult↗