Prognosis of medically stabilized unstable angina pectoris with a negative exercise test

Impact of diabetes in patients waiting for invasive cardiac procedures during COVID-19 pandemic

Background

During COVID-19 pandemic, elective invasive cardiac procedures (ICP) have been frequently cancelled or postponed. Consequences may be more evident in patients with diabetes.

Objectives

The objective was to identify the peculiarities of patients with DM among those in whom ICP were cancelled or postponed due to the COVID-19 pandemic, as well as to identify subgroups in which the influence of DM has higher impact on the clinical outcome.

Methods

We included 2,158 patients in whom an elective ICP was cancelled or postponed during COVID-19 pandemic in 37 hospitals in Spain. Among them, 700 (32.4%) were diabetics. Patients with and without diabetes were compared.

Results

Patients with diabetes were older and had a higher prevalence of other cardiovascular risk factors, previous cardiovascular history and co-morbidities. Diabetics had a higher mortality (3.0% vs. 1.0%; p = 0.001) and cardiovascular mortality (1.9% vs. 0.4%; p = 0.001). Differences were especially important in patients with valvular heart disease (mortality 6.9% vs 1.7% [p < 0.001] and cardiovascular mortality 4.9% vs 0.9% [p = 0.002] in patients with and without diabetes, respectively). In the multivariable analysis, diabetes remained as an independent risk factor both for overall and cardiovascular mortality. No significant interaction was found with other clinical variables.

Conclusion

Among patients in whom an elective invasive cardiac procedure is cancelled or postponed during COVID-19 pandemic, mortality and cardiovascular mortality is higher in patients with diabetes, irrespectively on other clinical conditions. These procedures should not be cancelled in patients with diabetes.

Consequences of canceling elective invasive cardiac procedures during Covid-19 outbreak

BACKGROUND

During COVID-19 pandemic in Spain, elective procedures were canceled or postponed, mainly due to health care systems overwhelming.

OBJECTIVE

The objective of this study was to evaluate the consequences of interrupting invasive procedures in patients with chronic cardiac diseases due to the COVID-19 outbreak in Spain.

METHODS

The study population is comprised of 2,158 patients that were pending on elective cardiac invasive procedures in 37 hospitals in Spain on the 14th of March 2020, when a state of alarm and subsequent lockdown was declared in Spain due to the COVID-19 pandemic. These patients were followed-up until April 31th.

RESULTS

Out of the 2,158 patients, 36 (1.7%) died. Mortality was significantly higher in patients pending on structural procedures (4.5% vs. 0.8%, respectively; p < .001), in those >80 year-old (5.1% vs. 0.7%, p < .001), and in presence of diabetes (2.7% vs. 0.9%, p = .001), hypertension (2.0% vs. 0.6%, p = .014), hypercholesterolemia (2.0% vs. 0.9%, p = .026) [Correction added on December 23, 2020, after first online publication: as per Dr. Moreno's request changes in p-values were made after original publication in Abstract.], chronic renal failure (6.0% vs. 1.2%, p < .001), NYHA > II (3.8% vs. 1.2%, p = .001), and CCS > II (4.2% vs. 1.4%, p = .013), whereas was it was significantly lower in smokers (0.5% vs. 1.9%, p = .013). Multivariable analysis identified age > 80, diabetes, renal failure and CCS > II as independent predictors for mortality.

CONCLUSION

Mortality at 45 days during COVID-19 outbreak in patients with chronic cardiovascular diseases included in a waiting list due to cancellation of invasive elective procedures was 1.7%. Some clinical characteristics may be of help in patient selection for being promptly treated when similar situations happen in the future.

The evaluation and management of dyslipidemia and impaired glucose metabolism during acute coronary syndromes

Dyslipidemia and hyperglycemia are common among patients presenting with acute coronary syndromes (ACS), and patients with ACS and metabolic disorders are at increased risk for worse outcomes. Although guidelines for the diagnosis and management of dyslipidemia, diabetes, and the metabolic syndrome have been published, these guidelines have not specifically focused on the ACS patient population. Recent observational registries and clinical trials have advanced the appreciation of these disorders in ACS populations and data from these studies support aggressive efforts to diagnose and treat dyslipidemia and hyperglycemia in patients admitted for ACS.

Prognosis of patients with unstable angina and low-risk exercise test: significance of ST-segment depression on the admission ECG

The presence of ST-segment depression on the admission electrocardiogram (ECG) is an important predictor of poor outcome in patients with unstable angina. On the other hand, patients with unstable angina who undergo a low-risk exercise test are supposed to have a favorable prognosis. The objective of the study was to determine the prognostic significance of ST-segment depression on the admission ECG in patients with unstable angina who undergo an exercise test that indicates a low risk of events. An interpretable exercise test was performed in 257 patients with primary unstable angina. A low-risk exercise test was completed by 156 (60%) patients and medical therapy was planned for all these patients. A multivariate analysis was performed in order to determine the independent predictors of events (cardiac death, nonfatal acute myocardial infarction, or admission for unstable angina) during a 12-month follow-up. Among patients with a low-risk exercise test, there were no significant differences between patients with and without ST-segment depression on the presenting ECG with regard to event rate (34 vs. 29%, P=NS). In multivariate analysis, ST-segment depression was not related to a higher incidence of events. Our findings appear to indicate that the presence of ST-segment depression on the admission ECG loses its prognostic significance in patients with primary unstable angina if they complete a low-risk exercise test.

[Clinical predictors of the presence of perfusion defects in more than than one territory in myocardial scintigraphy with GATED-SPECT]

BACKGROUND AND OBJECTIVE

Extension of perfusion defects is associated with outcome in patients undergoing myocardial scintigraphy. The study aimed to identify the clinical characteristics that can predict the existence of perfusion defects in more than one territory in patients referred for myocardial scintigraphy with GATED-SPECT.

PATIENTS AND METHODS

A total of 193 patients undergoing myocardial scintigraphy with GATED-SPECT (99mTc-tetrofosmine) were studied. Clinical variables and scintigraphy results were studied to determine what clinical variables are associated with perfusion defects in more than one territory.

RESULTS

The number of territories with perfusion defects per patient was 1.1 0.8 and 29% had perfusion defects in > 1 territory. Patients with greater probability of having perfusion defects in > 1 territory were those with previous myocardial infarction (44% vs 21%, p = 0.030) and males (33% vs 10%, p = 0.006). In addition, patients with > 2 coronary risk factors had a statistical tendency to have defects in > 1 territory (47% vs 20%, p = 0.057). Only 15% of the patients with one of these three characteristics had perfusion defects in > 1 territory in comparison with 45% and 83% in those with 2 or 3 factors, respectively.

CONCLUSION

Considering 3 simple clinical characteristics (male gender, previous infarction and existence of > 2 coronary risk factors), it is possible to predict which patients are more likely to show perfusion defects in > 1 territory during GATED-SPECT myocardial scintigraphy.

[Chest pain unit: one-year follow-up]

INTRODUCTION AND OBJECTIVES

In Spain there is little information available about chest pain units for the treatment of patients of low-to-medium risk with suspected acute coronary syndrome.

PATIENTS AND METHOD

A prospective study was performed among emergency room patients who complained about acute chest pain and were suspected of suffering an acute coronary syndrome with a normal or unspecific initial evaluation. They underwent an early submaximum stress test to decide on possible hospitalization. The follow-up time was 1 year.

RESULTS

Of 472 emergency room patients with suspected acute coronary syndrome, 179 performed the stress-test during the first hours of the triggering chest pain episode. None met the high-risk criteria for unstable angina. In 78.8% of the cases, the test results were negative and the patients were discharged. The results were positive in 15.1% and inconclusive in 6.1%; there were no complications during the procedure. Patients with a negative stress test had a more favorable outcome than the rest, with fewer following visits to the emergency room (11% vs 22%, p<0.001). One patient with a negative stress test died of a non-cardiovascular complication. None of the patients suffered acute myocardial infarction during follow-up and 89% of the patients with negative stress test had a favorable outcome (in terms of visits to the emergency room, unstable angina, acute myocardial infarction, or cardiovascular death).

CONCLUSIONS

Chest pain units for the care of low-to-medium risk patients with acute chest pain allow a fast and safe hospital release with a favorable mid-term outcome.

The exercise test that indicates a low risk of events. Differences in prognostic significance between patients with chronic stable angina and patients with unstable angina

OBJECTIVES

The objective of this prospective study was to determine the differences in the prognostic significance of an exercise test (ET) that indicates a low risk of events (low-risk exercise test [LRET]) between patients with unstable angina (UA) and those with chronic stable angina (CSA).

BACKGROUND

It is not known whether the prognostic significance of an LRET is influenced by the disease; that is the reason for performing exercise testing.

METHODS

All patients not presenting with high-risk criteria were submitted to a prognostic ET. The ET was performed by patients with CSA and patients with primary UA stabilized with medical therapy. Medical therapy was planned for all patients. A combined end point was defined as cardiac death, nonfatal acute myocardial infarction or hospital admission for UA. Multivariate analysis was performed to determine the independent predictors of events.

RESULTS

Low-risk criteria were fulfilled by 105 patients with UA and 86 patients with CSA. The mean follow-up time was 347 +/- 229 days. The event rate was higher in the UA group than in the CSA group (28% vs. 9%, p = 0.001). The CSA group showed worse ET results. Performance of ET by patients with UA was the principal predictor of events (odds ratio 4.2, p = 0.0005).

CONCLUSIONS

Among patients who underwent an LRET, those with UA had a rate of events significantly higher than that of patients with CSA, despite the worse results of ET in patients with CSA.

[In-hospital evolution and current prognosis of unstable angina]

INTRODUCTION AND PROGNOSIS

The prognosis of patients with unstable angina has improved in recent years resulting in a progressive reduction in hospital stay and treatment. The aim of this study was to know the current prognosis of patients with unstable angina in a non-selected population followed for up to 3 months.

PATIENTS AND METHODS

478 consecutive patients with unstable angina were studied. They were treated following a strict protocol and a management policy guided by symptoms and the results of an exercise test or a pharmacological stress test performed before hospital discharge.

RESULTS

The mean age was 66 +/- 11 years with 30% being females. Thirty-five percent had a prior history of myocardial infarction, 61% presented ischemic changes on the admission ECG, and 16% had elevation of the CK-MB plasma levels. An echocardiogram was performed in 80% of the patients, a stress test in 62%, coronary angiography in 51%, and a revascularization procedure in 27% of the patients. During hospitalization, the incidence of mortality or myocardial infarction, refractory angina or ischemic complications was of 3.6%, 11% and 13%, respectively. After hospital discharge and during a 3-month follow-up, the incidence of these complications was of 3.3%, 9% and 10% (NS compared to the in-hospital period). Overall, from the time of hospital admission to the 3-month follow-up, 4.2% of the patients died, 7% died or had an infarction, 20% had refractory angina, and 26% had some ischemic complication.

CONCLUSION

The in-hospital prognosis of unstable angina is currently good. However, patients discharged from hospital after stabilization, present an important number of ischemic complications during the following 3 months, similar to that presented by all patients during the acute phase.

Dobutamine stress echocardiography and exercise electrocardiography for risk stratification in medically treated unstable angina

Previous reports have demonstrated the superiority of exercise echocardiography over exercise electro-cardiography (ex-ECG) for risk stratification in patients with medically stabilized unstable angina (UA). We sought to analyze the prognostic value of dobutamine stress echocardiography (DSE) compared with ex-ECG for risk stratification in patients with UA.

METHODS

Ninety-two patients with medically treated UA were studied (mean age 65 +/- 11 years, 24 women, 42% of patients had electrocardiographic abnormalities on admission). Dobutamine stress echocardiography and treadmill ex-ECG were performed on the third day after hospital admission. End points were recurrent UA, myocardial infarction (MI), or cardiac death.

RESULTS

Mean follow-up was 24 +/- 7 months. During follow-up, 22 patients had cardiac events (18 recurrent UA, 2 MI, 2 cardiac deaths). The event-free survival rate was 80% for patients with negative DSE results for ischemia and 52% for those with positive DSE results (log rank 9.57; P =.002), compared with an event-free survival rate of 79% for patients with negative ex-ECG results and 66% for those with positive ex-ECG results (log rank 2.06; P = not significant). Left ventricular dysfunction (P =.01) and a positive dobutamine stress echocardiogram (P =.03), but not a positive exercise electrocardiogram, were independent predictors of cardiac events during follow-up.

CONCLUSIONS

Dobutamine stress echocardiography performed early in medically treated patients with UA predicts cardiac events during follow-up more accurately and with more specificity than ex-ECG does in this population.

Glycoprotein IIb/IIIa receptor blockade improves outcomes in diabetic patients presenting with unstable angina/non-ST-elevation myocardial infarction: results from the Platelet Receptor Inhibition in Ischemic Syndrome Management in Patients Limited by Unstable Signs and Symptoms (PRISM-PLUS) study

BACKGROUND

Diabetic patients who present with unstable angina or non-ST-elevation myocardial infarction suffer a substantially greater incidence of subsequent infarction or death compared with nondiabetic patients. The present study was undertaken to examine whether diabetic patients in the Platelet Receptor Inhibition in Ischemic Syndrome Management in Patients Limited by Unstable Signs and Symptoms (PRISM-PLUS) study appeared to benefit from platelet glycoprotein IIb/IIIa receptor-mediated inhibition of platelet aggregation by tirofiban.

METHODS AND RESULTS

Of the 1570 PRISM-PLUS patients treated with either tirofiban plus heparin (n=773) or heparin alone (n=797), approximately 23% in each treatment group were diabetic. A comparison of treatment outcomes in the diabetic subgroup revealed that the combination therapy compared with heparin alone was associated with reductions in the incidence of the composite primary end point of death, myocardial infarction (MI), or refractory ischemia at 2, 7, 30, and 180 days (7.7% versus 8.3%, 14. 8% versus 21.8%, 20.1% versus 29.0%, and 32.0% versus 39.9%, respectively; P=NS) and in the incidence of MI or death (0.0% versus 3.1%, P:=0.03; 1.2% versus 9.3%, P:=0.005; 4.7% versus 15.5%, P:=0. 002; and 11.2% versus 19.2%, P:=0.03). Tests for quantitative interaction between tirofiban therapy and diabetic status were significant.

CONCLUSIONS

The addition of tirofiban to heparin and aspirin appears effective in the prevention of major ischemic events, particularly MI or death, in diabetic patients presenting with unstable angina and non-ST-elevation MI.

Unstable Angina

The recent availability of novel antiplatelet and antithrombin agents has revolutionized the therapeutic options for intermediate- and high-risk unstable angina (UA). Current guidelines recommend aspirin, unfractionated heparin (UFH), and antianginal therapy. Low-molecular-weight heparin (LMWH) and direct thrombin inhibitors have significant theoretical advantages and apparent clinical benefits compared with UFH and are good alternatives in selected patients. Glycoprotein (GP) IIb/IIIa receptor inhibition reduces the future risk of myocardial infarction (MI) and may reduce the incidence of death in patients with unstable angina. In particular, these drugs should be considered for use in combination with aspirin and UFH in patients undergoing an "early invasive" approach. Coronary revascularization plays an important role in high-risk patients and in those with refractory angina, but its routine application continues to be controversial. Issues regarding the use of LMWH in combination with GP IIb/IIIa inhibitors and during percutaneous transluminal coronary angioplasty (PTCA) are being addressed in clinical trials. Ideally, the incidence of serious cardiac events in patients with UA will continue to decrease with the ongoing search for potent drug combinations that achieve early control of intracoronary thrombosis.

Determinants of a positive exercise test in patients admitted with acute non-infarct chest pain

BACKGROUND AND OBJECTIVES

Some patients with suspected unstable angina show ischemia at the exercise treadmill test despite having been medically stabilized. The objective of this study was to determine clinical characteristics predicting a positive exercise treadmill test in patients with suspected unstable angina after medical stabilization.

METHODS

In 885 hospitalized patients with medically stabilized unstable angina, the relationship between the result of the pre-discharge exercise treadmill test and clinical characteristics was studied.

RESULTS

Mean age was 62+/-9 years and 668 (75%) were male. Exercise test was positive (chest pain and/or ST depression > or =1 mm) in 288 patients (33%). Univariate analysis showed the following associated with ischemia at the exercise test: male gender (56% vs. 20%, P<0.001 ), diabetes mellitus (41% vs. 31%, P=0.009), previous unstable angina (41% vs. 24%, P=0.001), previous stable angina (44% vs. 30%, P<0.001), previous coronary artery bypass grafting (43% vs. 31%, P=0.043), peripheral artery disease (45% vs. 31%) and progressive angina (55% vs. 31%, P<0.001). Multivariate analysis showed the following as independent predictors of ischemia: male gender (OR=2.25), diabetes (OR=4.12), previous unstable angina (OR=3.89), previous stable angina (OR=3.74) and progressive angina (OR=4.05).

CONCLUSIONS

In patients with suspected unstable angina, after medical stabilization: (1) the exercise treadmill test is positive in one-third of cases; (2) male gender, diabetes, previous angina (unstable and stable) and progressive angina are independent predictors of ischemia.