Infarct Zone Regional Wall Motion Research Articles

The relationship between collateral blood flow and infarct zone regional wall motion in patients with recent acute myocardial infarction

After acute myocardial infarction (AMI), the most significant prognostic determinants of myocardial viability and function are deterioration degree of the distal myocardial microcirculation and collateral flow. Quantification of coronary collateral circulation is possible by using intracoronary pressure measurement techniques. We hypothesized that quantitatively determined coronary wedge pressure (CWP) and collateral flow index (CFI) may be useful in order to designate regional left ventricular function and indirectly viability after MI. In this study, we investigated the relationships between angiographically quantified wall motion scores and CWP and CFI in patients with recent AMI and treated with thrombolytic therapy. Forty patients early after myocardial infarction with ≥60% residual stenosis in infarct related artery (IRA) after thrombolysis, who underwent PTCA and/or stent implantation for this culprit lesion, were included in this study. None of the patients had significant stenosis in other coronary arteries. Angiographic ventricular wall motion scoring (WMS) was performed semi quantitatively according to coronary artery surgery study criteria. After angiography, fiberoptic pressure monitoring guide wire (pressure wire, Radi) was positioned distal to the stenosis to be dilated. During complete occlusion with balloon inflation distal pressure recorded as CWP. CFI was determined as the ratio of simultaneously measured CWP to aortic pressure. The mean values of CWP, CFI and mean WMS were 18.1 ± 7.9 mmHg, 0.18 ± 0.09 and 3.15 ± 0.8, respectively. The CWP (r: −0.86) and CFI (r: −0.84) values correlated well with WMS determined in the infarcted territory. We concluded that collateral circulation in the infarcted region is related to the left ventricular regional function. Presence of adequate and intact collateral network in the infarct related segments diminishes microvascular damage translating into preserved left ventricular regional functions.

Impact and Determinants of Left Ventricular Function in Patients Undergoing Primary Percutaneous Coronary Intervention in Acute Myocardial Infarction

We evaluated the prognostic effect of baseline left ventricular function and the determinants of its recovery after acute myocardial infarction (AMI) treated by primary angioplasty. Left ventriculography was performed during the index procedure in 1,620 of 2,082 patients (78%) who underwent primary angioplasty for AMI in the CADILLAC trial. One-year survival rate was significantly lower in patients whose baseline left ventricular ejection fraction (LVEF) was <40% than in those whose LVEF was > or =40% (89.0% vs 97.2%, respectively, p <0.0001). The effect of baseline left ventricular dysfunction on mortality was confined to the first 3 months after AMI; thereafter, survival was independent of baseline LVEF. By multivariate analysis, baseline LVEF (hazard ratio 0.93, 95% confidence interval 0.90 to 0.97, p <0.001) and infarct zone regional wall motion (hazard ratio 2.67, 95% confidence interval 1.08 to 6.63, p = 0.03) were independent predictors of 1-year mortality. Seven-month convalescent LVEF was also directly related to baseline LVEF and inversely correlated with previous AMI, multivessel coronary disease, preprocedural Thrombolysis In Myocardial Infarction grade 0 to 2 flow, larger infarct artery diameter, and infarct artery restenosis at follow-up. In conclusion, baseline left ventricular function measured during the index procedure is a strong independent predictor of early and late survival after primary angioplasty. Simple clinical and angiographic features readily available at the time of primary angioplasty also predict convalescent LVEF and are thus of prognostic utility.

The relationship between collateral blood flow and infarct zone regional wall motion in patients with recent acute myocardial infarction

The relationship between collateral blood flow and infarct zone regional wall motion in patients with recent acute myocardial infarction

Corrected TIMI frame counts correlate with stenosis severity and infarct zone wall motion after thrombolytic therapy

Background The majority of patients with patent infarct-related arteries after thrombolytic therapy have slower than normal flow, which relates to myocardial perfusion. Methods To evaluate the relationships between blood levels of creatine kinase (CK) and the corrected Thrombolysis in Myocardial Infarction (TIMI) frame count (CTFC), infarct artery stenosis, and left ventricular function, we studied 397 patients with a first myocardial infarction who underwent angiography at 3 weeks. TIMI flow grades, the CTFC, infarct artery stenosis, and infarct zone wall motion (by contrast ventriculography using the centerline method) were assessed, and CK levels (in units per liter) were measured hourly for the first 4 hours after streptokinase (1.5 × 106 U over 30-60 minutes) and then every 4 hours over the next 20 hours, all blinded to treatment and outcome. Results Infarct artery stenosis and the CTFC, assessed as continuous variables, correlated in patients with patent infarct arteries (r = 0.33, P <.001). Also, there was a significant correlation between the CTFC and the sum of hypokinetic chords in the infarct zone (r = 0.15, P =.01). Patients with total occlusion or markedly slowed infarct artery flow (CTFC >100) had a higher fraction of chords with wall motion >2 SDs below normal (0.65 [0.41, 0.80] vs 0.37 [0.0, 0.67]) compared with patients with normal flow (CTFC ≤27) (P <.001). The rates of increase of median CK levels with respect to TIMI flow grades were 342 U/L/h for TIMI 3 versus 212 U/L/h for TIMI 2 versus 140 U/L/h for TIMI 0-1 (P <.0001). Conclusions Prolonged corrected TIMI frame counts correlate with stenosis severity in the infarct artery after infarction, infarct zone regional wall motion, and CK levels. (Am Heart J 2001;141:586-91.)

Significance of a coronary artery with Thrombolysis in Myocardial infarction grade 2 flow “patency” (outcome in the Thrombolysis and Angioplasty in Myocardial Infarction trials)

To determine whether pharmacologic reperfusion to Thrombolysis in Myocardial Infarction (TIMI) grade 2 flow during acute myocardial infarction confers the same clinical benefit as restoration of TIMI 3 flow, in-hospital clinical and angiographic outcomes in 1,229 patients prospectively enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction trials were analyzed. Patients were treated with intravenous tissue plasminogen activator or urokinase, or both. Angiography of the infarct-related artery 90 minutes after initiation of thrombolytic therapy demonstrated TIMI grades 0, 1, 2, or 3 flow in 20%, 7%, 17%, and 55% of vessels, respectively. Rescue or adjunctive coronary angioplasty was performed in 80%, 27%, and 16% of patients with TIMI 0/1, 2, or 3 flow, respectively. Predischarge angiography was performed in 963 patients. A significant gradient of increasing mortality was seen in patients with lower TIMI flow (4.3%, 6.1%, and 10.1% with TIMI 3, 2, and 0/1 flow, respectively, p = 0.002). The incidence of congestive heart failure and recurrent ischemia was significantly higher in patients with TIMI 2 than with TIMI 3 perfusion (26% vs 19% for heart failure, p = 0.03; 23% vs 17% for recurrent ischemia, p = 0.05). Acute left ventricular ejection fraction and infarct zone regional wall motion were also significantly improved in patients with TIMI 3 than with TIMI 2 flow, with trends toward better improvement in global and regional function in the TIMI 3 group. These findings were not affected by the use of acute coronary angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Systolic left ventricular function after reperfusion therapy for acute myocardial infarction. Analysis of determinants of improvement. The TAMI Study Group.

Contrast ventriculograms of 542 patients treated with intravenous thrombolytic agents for acute myocardial infarction were examined to define changes in left ventricular ejection fraction and regional wall motion that occur during the first week after reperfusion therapy for acute myocardial infarction and define clinical, acute angiographic and treatment variables related to improvement in global and regional left ventricular function. Intravenous tissue-type plasminogen activator and/or urokinase was administered to 805 patients during acute myocardial infarction. Mean time from symptom onset to thrombolytic therapy was 3 hours (22 patients received therapy within the first hour). Acute and 7-day catheterization were performed. Paired left ventricular ejection fraction and centerline regional wall motion were available in 542 patients (67%). Stepwise, multivariable analysis of clinical, acute angiographic and treatment variables was used to develop two models: One related to improvement in left ventricular ejection fraction, and the second related to improvement in infarct zone regional function. Left ventricular ejection fraction did not change (51.2 +/- 11.1% for acute versus 51.9 +/- 11.0% for 1 week, p = 0.19). Improvement in infarct zone regional function was modest (14%) at 1 week (-2.54 +/- 1.07 standard deviation per chord for acute versus -2.17 +/- 1.24 at 1 week, p < 0.001). Subgroup analysis demonstrated modest improvement in ejection fraction (1.4 +/- 9.5%) and greater improvement in infarct zone function (19%) in patients with successful sustained reperfusion at 1 week. Depressed left ventricular ejection fraction and infarct zone regional wall motion at the acute study were strongly associated with improvement of these parameters at 1 week. Resolution of chest pain before acute catheterization, infarct-related artery flow at acute catheterization, and depressed regional wall motion in the noninfarct zone were associated with improvement in both ejection fraction and regional infarct zone function at 1 week. Notably, the time from the onset of symptoms to initiation of thrombolytic treatment was not related to subsequent improvement in ventricular function. Dramatic improvement in left ventricular systolic function is not common after thrombolytic therapy for acute myocardial infarction. Improvement in global and regional systolic function is most closely related to acutely depressed ventricular function and successful acute coronary recanalization. Thus, patients with the most myocardium in jeopardy and successful coronary reperfusion demonstrate the greatest improvement in global and infarct zone ventricular function. Overall, the magnitude of this improvement is modest, suggesting that the benefits of coronary reperfusion are not solely related to improvement in systolic left ventricular function.

Precordial ST segment depression predicts a worse prognosis in inferior infarction despite reperfusion therapy

The impact of associated precordial ST segment depression in inferior myocardial infarction on angiographic and clinical outcomes after thrombolytic therapy and selective coronary angioplasty was studied in 583 patients with acute myocardial infarction. Anterior infarction (Group I), inferior infarction with precordial ST segment depression (Group II) and inferior infarction without precordial ST segment depression (Group III) were present in 289, 135 and 159 patients, respectively.Precordial ST segment depression was more frequent in circumflex than right coronary infarct-retated arteries (44 [71%] of 62 versus 91 [40%] of 230; p = 0.000). Although acute patency rates were not statistically different, there was a trend toward different patency rates at day 7 (Group I 88%, Group II 84%, Group III 80%; p = 0.089) partly because of insignificantly higher reocclusion rates in inferior infarction without precordial ST segment depression (Group I 11%, Group II 10%, Group III 18%, p = 0.104).Infarct zone regional wall motion (standard deviations/ chord) in inferior infarction was lower with precordial ST segment depression, both acutely (Group I −2.8 ± 0.9, Group II −2.5 ± 1.2, Group III 2.0 ± 1.1; p = 0.000) and at day 7 (Group I −2.2 ± 1.1, Group II −2.3 ± 1.1, Group III −1.9 ± 1.3; p = 0.011). Precordial ST segment depression was associated with a lower ejection fraction in inferior infarction both acutely (Group 147 ± 11%, Group II 53 ± 11%, Group III 58 ± 9%; p = 0.000) and at day 7 (Group I 49 ± 12%, Group II 53 ± 10%, Group III 58 ± 8%; p = 0.000).Complication rates tended to be higher in inferior infarction when precordial ST segment depression was present. Mortality rates for Groups I, II and III were 8%, 6% and 5%, respectively. These results suggest that precordial ST segment depression in inferior infarction predicts a worse ventriculographic and clinical outcome despite reperfusion therapy.

Determinants of Left Ventricular Functional Recovery After Thrombolytic Therapy and/or Immediate Coronary Angioplasty in Acute Myocardial Infarction

To determine the effect of thrombolytic therapy and/or immediate coronary angioplasty (PTCA) on left ventricular function, 129 patients with acute transmural myocardial infarction were retrospectively studied. Treatment strategies included thrombolytic therapy alone (n = 29), PTCA alone (n = 41), and combined thrombolytic therapy and PTCA (n = 59). Left ventricular ejection fraction (LVEF) and infarct zone regional wall motion (RWM) were determined from contrast ventriculography obtained acutely and at day 7–10. In the overall group, there was a 2 ± 9% increase in LVEF (p &lt; 0.02) and a 0.7 ± 1.2 SD/chord increase in RWM (p &lt; 0.0001) between day 1 and day J‐10. Patients with a patent infarct vessel at day 7–10 had a more significant change (Δ) in LVEF (3 ± 8 vs −5 ± 9%, p = 0.0002) and RWM (0.8 ± 1.2 vs 0.1 ± 1.0 SD/chord, p &lt; 0.02) than patients with an occluded vessel. Patients with a residual stenosis &lt; 70% at day 7–10 manifested a greater ΔLVEF (3 ± 8vs‐5 ± 9%, p &lt; 0.01) and ΔRWN (0.9 ± 1.2 vs 0.1 ± 1.0 SD/ chord, p &lt; 0.05) than patients who were occluded. There was a negative correlation between residual stenosis and ΔRWM (p &lt; 0.04). Patients treated &lt; 3 hours after symptom onset demonstrated a more significant ΔRWM when compared to patients treated ≥ 3 hours (1.0 ± 1.3 vs 0.5 ± 1.1 SD/chord, p &lt; 0.04). Patients treated with combined thrombolytic therapy and PTCA were observed to have a greater ARWM than patients treated with thrombolytic therapy alone (0.8 ± 1.2 vs 0.2 ±0.9 SD/chord, p &lt; 0.05). Patients with an LVEF &gt; 40% demonstrated a more significant ΔLVEF than patients; ± 40% (7 ± 8vs 1 ± 8%, p &lt; 0.007). A significant improvement in ΔLVEF was noted only in patients with an anterior infarction when compared to patients with an inferior infarction. Age, sex, presence of multivessel disease, history of prior myocardial infarction, initial patency of the infarct vessel, and presence of collaterals had no effect on left ventricular function. Stepwise multiple regression identified residual stenosis, time to treatment, and the degree of initial global impairment as the major joint predictors of ventricular functional recovery. (J Interven Cardiol 1988:1:3)

Impact of different reperfusion modalities on ventricular function after acute myocardial infarction

Single-plane contrast ventriculography was performed on admission and before hospital discharge in more than 200 patients with acute myocardial infarction participating in a series of prospective clinical trials including intracoronary streptokinase, percutaneous transluminal coronary angioplasty (PTCA), intravenous tissue plasminogen activator (rt-PA) and thrombolysis (intravenous rt-PA or streptokinase) followed by PTCA. Both global ejection fraction (EF) and regional wall motion of the infarct zone were measured to assess serial changes. Patients treated with intracoronary streptokinase 3.6 +/- 1.8 hours after symptom onset had no increase in EF (mean change 1 +/- 6%, difference not significant [NS]), but patients treated with primary PTCA at 3.0 +/- 1.2 hours did (mean improvement 8 +/- 7%, p less than 0.001). Patients treated with sequential intravenous streptokinase and PTCA 2.6 +/- 1.3 hours after symptom onset showed similar improvement in EF (mean change 6 +/- 12%, p less than 0.002). Patients treated with rt-PA had no change in EF whether treated with rt-PA alone or rt-PA followed by immediate angioplasty (mean change -2 +/- 8% and 0.5 +/- 8%, p = NS, respectively). When angioplasty was used in patients with persistent occlusion after thrombolytic therapy, EF improved in those who had received intravenous streptokinase (mean change 10 +/- 7%, p less than 0.002), but not those who had received rt-PA (+0.5%, p = NS). However, infarct zone regional wall motion improved in patients treated with intracoronary streptokinase (+0.59 +/- 0.79 standard deviation/chord, p less than 0.05), primary PTCA (+1.32 +/- 1.32, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Early reperfusion therapy improves left ventricular function after acute inferior myocardial infarction associated with right coronary artery disease

Quantitative global and regional ventriculographic analysis was performed acutely and 1 week later in 46 patients undergoing reperfusion procedures within 6 hours of acute inferior myocardial infarction due to right coronary artery disease. While serial improvement in global left ventricular ejection fraction was not demonstrated for the group, infarct zone regional wall motion did improve (−2.7 ± 0.9 vs −2.3 ± 1.4 SD/chord, p < 0.007). Serial improvement in global ejection fraction was demonstrated in the subgroup of patients treated within 2 hours of symptom onset (55 ± 10 vs 62 ± 10%; n = 5; p < 0.03). Infarct zone regional wall motion improved serially only in the subgroup of patients treated within 3 hours of symptom onset (−2.4 ± 1.1 vs −1.3 ± 1.7 SD/chord; n = 11; p < 0.007). Patients with initially patent arteries had a higher ejection fraction on follow-up catheterization than did those with initially occluded vessels (61 ± 11 vs 55 ± 7%; p < 0.02), and patients with patent arteries at follow-up had a higher ejection fraction than did those whose arteries were occluded (60 ± 9 vs 48 ± 4%; p < 0.0001). We conclude that significant improvement in global and reglonal left ventricular function in patients with inferior myocardial infarction is possible when reperfusion therapy is begun early or when arterial patency is achieved.