Holter monitor ST segment evaluation in hospitalized patients with unstable angina

The correlation of angina attacks with ST segment changes detected during ambulatory Holter monitoring was evaluated in patients with unstable angina. Forty hospitalized patients had one to three 24-hour Holter recordings each. Twenty-three patients had a cardiac catheterization, confirming significant coronary artery disease. The Holter recordings, scanned blindly by computer, were evaluated for ST segment shifts (defined as +/- 1.5 mm from baseline, lasting 60 seconds or longer). Angina attacks were carefully logged. Over the total forty patient experience, only 15 of 74 (20.3%) angina attacks had corresponding ST segment shifts on the Holter recordings. Nine of 34 (26.5%) angina attacks in the 23 patients who had a cardiac catheterization had corresponding ST segment shifts. A total of 159 ST segment shifts were recorded on these forty patients, but only 15 (9.4%) ST shifts corresponded to a time when the patients were actually experiencing angina attacks. The performance of the test procedure was quantified by use of Youden's J statistic. The aggregate J, over all patients, was 0.203 (J = 1.0 is perfect, J = 0.0 is useless). When consideration was restricted to patients with cardiac catheterization, the aggregate experience J was 0.263. Dealing with only the patients who had angina attacks during the monitoring, and computing the J statistic for each individual patient, the resulting mean J statistic was 0.146, with SEM = 0.0731. The Holter monitoring worked reasonably well in only 2 of the 14 patients who gave clear tests of the procedure. In an attempt to improve the performance of the procedure, 21 Holter recordings in eight patients were reread for ST segment shifts of only +/- 1 mm from baseline, lasting 30 seconds or longer. In these eight patients with rescanned Holter recordings, only five of 17 (29.4%) angina attacks resulted in an ST segment shift. In conclusion, ambulatory Holter recordings proved not to be a suitable method of documenting ST segment shifts during angina attacks in this study.     

ST segment response to acute coronary occlusion: coronary hemodynamic and angiographic determinants of direction of ST segment shift

To assess the relationship between the direction of ST segment response to transient coronary occlusion and collateral function, we studied 25 patients with diagnostic ST segment changes during transient occlusion of the proximal left anterior descending artery (LAD). Electrocardiographic leads I, II, V2, and V5; left ventricular filling, aortic, and distal coronary pressures; and great cardiac vein flow were measured during percutaneous transluminal coronary angioplasty (PTCA) of the LAD. During a 1 min LAD balloon occlusion, 16 patients had reversible ST elevation (group I) and nine patients had ST depression (group II). The ST responses in individual patients were consistent during repeated occlusions, and ST depression never preceded ST elevation. Angiography before PTCA showed less severe LAD stenosis in group I (69 +/- 15%) than in group II (88 +/- 10%; p less than .01) and collateral filling of the LAD in no group I patient but in six of nine patients in group II (p less than .01). During LAD occlusion, determinants of myocardial oxygen demand (left ventricular filling pressure, aortic pressure, heart rate, and double product) were similar in both groups. Group I patients, however, had lower distal coronary pressure (25 +/- 8 vs 41 +/- 16 mm Hg) and residual great cardiac vein flow (33 +/- 14 vs 51 +/- 22 ml/min) and higher coronary collateral resistance (3.1 +/- 2.1 vs 1.5 +/- 0.8 mm Hg/ml/min) than group II patients (all p less than .05). In patients with ST elevation during LAD occlusion, stenosis before PTCA was less severe, visible collaterals were not present, and hemodynamic variables during LAD occlusion reflected poorer collateral function.(ABSTRACT TRUNCATED AT 250 WORDS)     

Relation between ST segment shifts during ischemia and thrombin activity in patients with unstable angina

This study was designed to determine in patients with unstable angina whether specific electrocardiographic abnormalities associated with ischemia, the presence of coronary lesions consistent with thrombosis on angiography or the presence of recurrent ischemia reflects increases in thrombin activity as manifested by increased plasma concentrations of fibrinopeptide A. The concentration of fibrinopeptide A in plasma was increased to 6.7 +/- 3.1 nM for the group as a whole (n = 29). Increases were greater in the 17 patients who exhibited reversible ST segment shifts (10.2 +/- 5.2 nM) than in the 12 patients exhibiting reversible T wave abnormalities alone (1.6 +/- 0.2 nM) (p less than 0.01). Nine of the 17 patients with reversible ST segment shifts who underwent coronary angiography had lesions with morphologic characteristics consistent with atherosclerotic plaque complicated by thrombosis compared with only 2 of 9 patients with T wave changes only (p less than 0.05). Plasma concentrations of fibrinopeptide A were markedly elevated in 7 of the 11 patients in whom complex lesions were noted on angiographic examination. Thus, the occurrence of reversible ST segment shifts identifies a group of patients with unstable angina in whom ongoing thrombosis is likely and who may be particularly likely to benefit from antithrombotic therapy.     

Role of resting thallium201 perfusion in predicting coronary anatomy, left ventricular wall motion, and hospital outcome in unstable angina pectoris

We performed quantitative thallium scintigraphy in 66 unstable angina patients, 5.6 +/- 5.1 hours after rest pain, to predict coronary anatomy, left ventricular wall motion, and hospital outcome. Thallium defects and/or washout abnormalities were present in 5 of 10 (50%) patients with coronary stenoses less than 50%, 27 of 33 (82%) patients with coronary stenosis greater than or equal to 50% and no history of previous myocardial infarction, and in 23 of 23 patients (100%) with histories of previous infarction. Defects were uncommon in the territory of vessels with less than 50% (13 of 61, 21%), but significantly more common in the territory of vessels with greater than or equal to 50% stenosis (57 of 137, 42%), p less than 0.005. With the addition of washout abnormalities to defect analysis, sensitivity for detection of coronary stenoses improved to 67% (92 of 137), p less than or equal to 0.005, but specificity fell to 59% (36 of 61), p less than 0.01. Segmental wall motion abnormalities were less common in segments with normal perfusion (21%) or in those with washout abnormalities alone (19%), than in segments with thallium defects (45%, p less than 0.005). Defects in patients with previous infarction were common in both segments, with normal (26 of 66, 40%) or abnormal (24 of 45, 53%) wall motion. Eleven of 18 patients with in-hospital cardiac events, but no history of myocardial infarction, had resting thallium defects, whereas only 8 of 25 patients without cardiac event had thallium defect (p = 0.056).(ABSTRACT TRUNCATED AT 250 WORDS)     

Transient electrocardiographic changes in patients with unstable angina: Relation to coronary arterial anatomy

The relation between the spontaneous electrocardiographic changes and coronary arterial anatomy in unstable angina pectoris was examined in 97 patients with coronary artery disease and transient electrocardiographic changes during chest pain. Sinus rhythm was maintained during pain in all patients. Heart rate increased significantly in 61 percent (mean ± standard error of the mean 72 ± 2 to 93 ± 2 beats/min, probability [p] < 0.001) and was unchanged or decreased in 39 percent of patients (73 ± 2 to 72 ± 2 beats/min; p = not significant) during pain. S-T segment changes developed in 97 percent of patients, of whom 42 percent had S-T segment elevation and 55 percent S-T depression. The magnitude of the S-T segment shift was greater in patients with triple vessel disease (2.2 ± 0.4 mm) than in those with double (1.5 ± 0.1 mm) or single (1.4 ± 0.1 mm) vessel disease (p < 0.05). In 43 patients with single vessel disease S-T segment elevation developed in 78 percent of those with right coronary artery disease and in only 9 percent of those with left circumflex disease (p < 0.02). Maximal S-T segment changes were more frequent in the inferior leads in patients with right coronary artery disease (56 percent) and in the anterior leads in patients with left anterior descending (65 percent) and circumflex (64 percent) disease (p < 0.05).Thus, patients with coronary artery disease and unstable angina maintain regular sinus rhythm during chest pain, and the heart rate usually increases but may be unchanged or decreased in a significant proportion. S-T segment elevation is common in these patients and the magnitude of the S-T segment shift is related to the extent of the underlying coronary disease. This study suggests that the type and distribution of the repolarization changes are a reflection of the location and severity of the atherosclerotic process.     

Changes in the ST segment in unstable angina pectoris. Its prognostic value

Out of 145 patients with unstable angina hospitalized at CCU of the Instituto de Cardiologia do Rio Grande do Sul (Brazil) in 1981, 69 were studied: group I = 23 case (33.3%) with transient ST segment depression, group II = 13 cases (18.8%) with transient ST segment elevation, group III (control) = 33 cases (47.8%) without acute EKG changes. Group I showed a higher incidence of double-triple coronary artery involvement: 71.4% VS 53.8 and 63.3% respectively (non significant). This group also showed a higher number of patients with severe angina and who suffered acute myocardial infarction during follow-up, although without statistical significance. There were 8 deaths (34.8%) in group I, 3 (23.1%) in group II and 4 (12.1%) in group III (chi 2 = 4.11, p greater than 0.05). The 36 months survival rate was lower in group I than in groups II and III: 52.9% VS. 75.2% (NS) and 89.7% (P less than 0.02) respectively. We conclude that acute EKG changes, mainly transient ST segment depression, in unstable angina, are markers of high risk patients.     

Relation of therapeutic response to nifedipine to coronary anatomy and motion of S-T segment during unstable angina pectoris

Of 77 patients hospitalized for unstable angina pectoris and failure of oral, dermal, or intravenous nitrates and/or beta blockade, 81 percent with negligible or single-vessel disease and 55 percent with two- or three-vessel disease showed response (p < 0.05) to nifedipine therapy. Patients with either S-T elevation or no change during pain responded better (31 of 45) than those with any S-T depression (16 of 32; p < 0.05). Patients with negligible or singlevessel disease had a higher prevalence of S-T elevation ( 13 of 16) than patients with two- or three-vessel disease (15 of 31; p = 0.004). S-T motion did not predict response in patients with two- or three-vessel disease, but did predict response in patients with negligible or single-vessel disease. On follow-up study at 9 ± 8 (range one to 33) months, 39 of 42 who had shown response were free from pain. Three died from infarction without unstable angina. Five who showed response had elective bypass surgery. The addition of nifedipine abolished or reduced pain episodes by more than 50 percent in 61 percent of patients with refractory unstable angina pectoris. Patients with negligible or single-vessel disease with S-T elevation benefit most. In patients with two- or three-vessel disease, the type of S-T motion did not predict response. Follow-up of all those with response indicated sustained amelioration by nifedipine therapy. Failure of nifedipine therapy should not be accepted until a dose of 120 mg per day has been achieved, or until intolerable side effects appear.     

Correlation of remote ST segment depression and coronary anatomy during acute coronary occlusion

BACKGROUND: The appearance of remote ST segment depression (RSTD) on an electrocardiogram (ECG) is associated with more extensive infarction and a worse clinical outcome than when RSTD is absent. OBJECTIVE: To determine whether RSTD predicts coronary anatomy during acute coronary occlusion. It was hypothesized that RSTD is associated with the occlusion of a proximal lesion, an extensive artery and an artery without distal collateralization. PATIENTS AND METHODS: In 113 consecutive patients with single vessel disease undergoing percutaneous transluminal coronary angioplasty (PTCA), 12-lead ECGs (recorded at baseline and during balloon inflation) and angiographical data were analyzed independently. Patients with ST segment elevation in the primary territory and RSTD (greater than 1 mm ST depression at 80 ms after the J point) (group A) were compared with patients without RSTD (group B). Proximal lesions were defined as lesions located in the segments proximal to the acute marginal branch, first diagonal artery or first obtuse marginal branch. An extensive right coronary artery (RCA) was one that supplied the posterolateral wall; an extensive left anterior descending (LAD) artery was one that supplied the inferoapical wall; and an extensive circumflex artery was one that supplied the posterior descending artery. RESULTS: Fifty-four patients (48%) had PTCA of the proximal vessels, 43 patients (38%) had extensive target vessels and 11 patients (9.7%) had collaterals. Target vessels included 33% in RCA, 44% in LAD artery and 23% in circumflex artery. Forty-five patients (40%) developed RSTD during balloon inflation (group A). Patients in group A were more likely to have extensive vessels on the angiogram than those in group B (group A 49%, group B 31%; P=0.05). None of the patients in group A had collaterals to the culprit artery, while 16% of patients in group B did (P=0.003). The two groups were not significantly different with respect to the number of proximal lesions (group A 58%, group B 42%; P=0.08). Analysis performed according to the target artery revealed that RSTD was associated with occlusion of an extensive RCA during RCA occlusion (extensive RCA in group A 100%, group B 57%; P=0.006). For the LAD artery, RSTD was associated with proximal lesions (group A 74%, group B 41%; P=0.02) and absence of collaterals (group A 100%, group B 74%; P=0.01). CONCLUSIONS: During acute coronary occlusion, the presence of RSTD on 12-lead ECG was specific for the absence of collaterals. The presence of RSTD during RCA occlusion was strongly associated with an extensive RCA, suggestive of posterolateral wall ischemia. During LAD artery occlusion, the presence of RSTD was associated with proximal occlusion, which resulted in ischemia of the LAD artery and the major diagonal artery territories.     

Long-term outcome in patients with unstable angina treated by coronary balloon angioplasty

Comparison of balloon angioplasty results in 472 patients with stable angina (SA) and 158 patients with unstable angina (UA) in 5-year follow-up is reported. Clinical success rate did not differ significantly, while periprocedural complications rate was higher in UA group (22.3 vs. 11.1%, P<0.001). During follow-up UA patients demonstrated higher: restenosis rate (48.5 vs. 30.4%, P<0.001), incidence of myocardial infarction (8.8 vs. 3.0%, P=0.004), although cardiac mortality did not differ significantly (2.2 vs. 1.6%). Reintervention rate in patients with unstable angina resultant from restenosis or significant artherosclerosis progression in coronary vessels, or originating from both of them, was also higher (53.7 vs. 34.1%, P<0.001). Event-free survival was significantly lower in UA patients (43.4 vs. 61.3%, P=0.02). The uni- and multivariate analysis proved that unstable angina was an independent risk factor in restenosis, re-intervention and cardiac events rate, despite perceptible differences in the baseline characteristics. Sub-group analysis of UA patients according to Braunwald classification revealed lower success rate and higher incidence of myocardial infarction during follow-up in post-infarction angina (class C), whereas new onset, no-rest angina (class I) had higher event-free survival in comparison with rest angina (classes II and III). CONCLUSIONS: UA patients treated by balloon angioplasty had higher periprocedural complications rate, as well as restenosis and re-intervention rate. Despite higher cardiovascular events rate during 5-year follow-up in UA group, survival rate in both groups was high and cardiac mortality did not differ significantly. Unstable angina constitutes a strong independent risk factor in adverse long-term outcome.     

Left and right heart haemodynamics during spontaneous angina pectoris. Comparison between angina with ST segment depression and angina with ST segment elevation.

The function of both right and left sides of the heart was studied during spontaneous attacks of angina pectoris at rest in 7 patients showing ST depression (type I) and 4 showing ST elevation (type II) during the attack. In none of the 44 type I attacks and 29 type II attacks which were recorded did circulatory changes; the latter were different in the two groups. Type I attacks showed: a) a brief fall in arterial pressure, accompanied by b) a rise of right atrial and pulmonary wedge pressures and c) a decrease of cardiac output, right and left stroke work, the mean rate of systolic ejection, and indirect left ventricular pre-ejection dP/dt. In the course of the attack a hypertensive phase followed, which was paralleled by an increase of heart rate, cardiac output, left and right stroke work, and mean systolic ejection rate, left dP/dt; right atrial pressure and wedge pressure remained raised. All of the circulatory functions started to revert towards the pre-attack levels coincident with the waning phase of the electrocardiographic alteration, the latter occurring either spontaneously or after nitroglycerin. Type II attacks for the entire duration of the electrocardiographic changes showed: a) a reduction of arterial pressure, cardiac output, right and left stroke work, mean systolic ejection rate, and left dP/dt, b) a rise of right atrial and wedge pressures, and c) quite small changes of heart rate. When the electrocardiogram started to revert to the pre-attack aspect, the cardiac function rapidly improved and, after a supernormal phase, returned to the basal levels in about 2 minutes. It is concluded: 1) that no circulatory factor interfering with the mechanical effort of the heart is responsible for eliciting spontaneous angina: 2) that in type I attacks right and left ventricular impairment occurs which recovers rapidly, possibly through a sympathetic compensation; 3) that in type II attachs dysfunction of both sides of the heart occurs and persists throughout the episode of electrocardiographic alteration; 4) that the dynamic impairment is probably more severe in type I than in type II angina.     

ST段抬高为特点的劳力型心绞痛患者的冠脉造影和冠脉成形术治疗

报道４例以ＳＴ段抬高为特点的劳力性心绞中层得，探讨其冠脉病脉成形术治疗效果。方法术前行平板运动试验或记录心绞痛作发时的心电图，全部病例接受冠状动脉造影和ＰＴＣＡ术，术后作平板运动试验。本文结果亦证实ＰＴＣＡ或同时置入支架可完全缓解心绞痛和心肌缺血的心电表现。     

Exercise-induced ST segment elevation in a patient with effort angina pectoris and normal coronary arteries

A 32 year old woman who complained of exercise-induced chest pain was found to have widespread elevation of the ST segment of the electrocardiogram during exercise testing. Coronary angiography demonstrated no obstructive lesions and no evidence of coronary artery spasm despite ergonovine administration, bicycle ergometry and rapid atrial pacing. Exercise thallium-201 scintigraphy demonstrated no perfusion defects despite ST segment elevation. Radionuclide blood pool imaging revealed a slight decrease in ejection fraction with exercise. The available evidence raises the possibility of small vessel coronary artery disease, either structural or vasotonic, as a cause of this patient's symptoms.     

Ventricular arrhythmias in patients with rest angina: correlation with ST segment changes and extent of coronary atherosclerosis

Major ventricular arrhythmias occurring concurrently with myocardial ischemia are presumed to be the most frequent mechanism for sudden cardiac death. Two hundred eighteen catheterized patients with angina pectoris at rest were reviewed to identify clinical, ECG, and arteriographic features that might correlate with the presence of serious ventricular arrhythmias occurring during episodes of rest pain. Ventricular arrhythmias during episodes of rest pain were significantly more common in patients who manifested transient ST segment elevation in the anterior leads and in patients with marked transient ST segment shifts (greater than 5 mm). Ventricular arrhythmias during episodes of rest pain were not more common in patients with extensive coronary artery disease.     

ST段偏移在冠心病诊断中的临床意义研究

为探讨动态心电图ST段偏移对诊断冠心病的临床价值,观察经冠状动脉造影主要分支狭窄≥50％的62例冠心病组与101例正常健康老人组的最大ST段上抬、最大ST段下移、ST段偏移总和、ST段偏移总差等参数。结果两组间除ST段偏移总和外,其余参数均有显著性差异(P<0.001)。初步提示这些参数可作为诊断冠心病的鉴别诊断依据,但对上述参数的正常值范围尚需作进一步的研究。     

Rest angina with transient S-T segment elevation correlation of clinical features with coronary anatomy

In 44 consecutive patients with angina at rest associated with transient S-T segment elevation, clinical features were correlated with angiographic coronary anatomy. Patients were divided into three groups depending on the number of major vessels having ?70 per cent luminal narrowing: Group I = no or minimal disease (six patients); group II = single vessel disease (13 patients); and group III = multiple vessel disease (25 patients).The following features did not differ significantly among groups I, II or III: age, sex, risk factors, time from onset of episodes of pain at rest to study or arrhythmias during ischemic episodes. Patients in group III were more likely to have angina on effort (p < 0.001) and an abnormal base line electrocardiogram (p < 0.001) than patients in groups I or II. However, the absence of these features did not separate patients in group I from those in group II.In patients with angina at rest associated with transient S-T segment elevation, clinical features identify patients with multiple vessel disease but do not allow differentiation of patients with no or minimal coronary disease from patients with single vessel disease.     

Percutaneous transluminal coronary angioplasty in unstable angina: comparison with stable angina

Percutaneous transluminal coronary angioplasty was performed in 25 patients with unstable angina and in a similar group of 25 patients with stable angina. The frequency of single, double, and triple vessel disease was identical in each group. Technical success was achieved in 22 (81%) out of 27 attempts in those with unstable angina and in 14 (52%) out of 27 attempts in those with stable angina. Vessel occlusion occurred in nine patients, necessitating emergency bypass surgery in four. There was evidence of myocardial infarction in three patients in each group and one patient in the unstable group subsequently died. Twenty eight of 32 successfully treated patients were followed up by means of repeat coronary arteriography, exercise electrocardiography, and clinical assessment after a mean (SD) interval of 14 (7) months. There was angiographic evidence of restenosis in 32% (seven of 22) of lesions in the unstable group and 44% (four of nine) of lesions in the stable group. There were no late infarctions or deaths during the follow up period. These results support the growing evidence that angioplasty can be carried out safely and effectively in patients with unstable angina.     

Arteriographic features of angina pectoris associated with ST segment depression during coronary arterial spasm

To examine the angiographic features of vasospastic angina associated with ST segment depression, we attempted to analyze the coronary arteriograms of 12 patients who exhibited ST segment depression during the ergonovine provocative test. Right and left coronary arteriograms were obtained successively within a short period when the ergonovine administration revealed ST segment depression. Eight out of 12 patients showed non-total spastic obstructions in one of the major coronary arteries. Among them, a collateral augmentation was found only in one patient. Two cases exhibited the well-developed collateral channels during non-anginal periods and in one case a collateral blood supply was reduced by the spasm occurred in the donating artery. In another one, the collateral circulation did not change during anginal period. Three out of 4 patients who showed total spastic obstructions demonstrated transiently augmented collateral circulation which was supplied by the non-spastic artery. These findings may indicate that ST segment depression during coronary artery spasm could attribute to a subendocardial ischemia caused by an incomplete occlusion of large coronary artery and transient reduction or augmentation of collateral blood flow.     

Improving outcome over time of percutaneous coronary interventions in unstable angina

OBJECTIVE: This study was performed to evaluate the recent changes in the outcome of coronary interventions in patients with unstable angina (UA). BACKGROUND: An early invasive strategy has not been shown to be superior to conservative treatment in patients with UA. Earlier studies had utilized older technology. Interventional approaches have changed in the recent past, but to our knowledge, no large studies have addressed the impact of these changes on the outcome of coronary interventions. METHODS: We analyzed the in-hospital and intermediate-term outcome in 7,632 patients with UA who underwent coronary interventions in the last two decades. The study population was divided into three groups: group 1, n = 2,209 who had coronary intervention from 1979 to 1989; group 2, n = 2,212 with interventions from 1990 to 1993; and group 3, n = 3,211 treated from 1994 to 1998. RESULTS: Group 2 and 3 patients were older and sicker compared with group 1 patients. The clinical success improved significantly in group 3 (94.1%) compared with group 2 (87%) and group 1 (76.5%) (p < 0.001). There was a significant reduction in in-hospital mortality, Q-wave myocardial infarction and need for emergency bypass surgery in group 3 compared with the earlier groups. One-year event-free survival was also significantly higher in the recent group compared with the earlier groups: 77% in group 3, 70% in group 2 and 74% in group 1 (p < 0.001). With the use of multivariate models to adjust for clinical and angiographic variables, treatment during the most recent era was found to be independently associated with improved in-hospital and intermediate-term outcomes. CONCLUSIONS: There has been significant improvement in the in-hospital and intermediate-term outcome of coronary interventions in patients with UA in recent years; newer trials comparing conservative and invasive strategies are therefore needed.     

Dobutamine-induced ST segment elevation in a patient with angina at rest and critical coronary lesions.

A case of dobutamine-induced ST-segment elevation in a patient with angina at rest and severe two-vessel disease is described. Coronary angiography performed during the ischaemic episode showed patency of coronary arteries; ST-segment elevation and chest pain regressed after propranolol administration. This case suggests that in the presence of severe coronary lesions dobutamine may produce transmural myocardial ischaemia by increasing myocardial oxygen demand and inducing myocardial blood flow maldistribution.