Prognostic Value of Left Ventricular Global Strain Analysis by Two-Dimensional Speckle-Tracking Echocardiography in Non-Hemodynamically Significant Intermediate Coronary Lesions.

Intermediate coronary lesions represent a major challenge for the invasive and noninvasive cardiologist. Left ventricular strain calculation by speckle tracking echocardiography has the capacity to analyze the motion of the cardiac tissue. This study aimed to evaluate its usefulness and prognostic significance in nonhemodynamically significant intermediate coronary lesions. We studied 247 patients who underwent a clinically indicated coronary angiogram. Each of the patients had a single nonrevascularized nonhemodynamically significant intermediate severity coronary lesion (ISCL) with a fractional flow reserve greater than 0.80. The left ventricular global longitudinal strain (GLS) was calculated using speckle-tracking echocardiography with TomTec 2D Cardiac Performance Analysis (Unterschleissheim, Germany). An abnormal GLS was defined as less than -20%. The primary endpoints were revascularization of the target lesion, admissions for major adverse cardiac events (MACE), and cardiac-related mortality, all within 2 years. On multivariate logistic regression data analysis, we found that patients with an ISCL and abnormal GLS had an increased risk for admissions due to MACE (odds ratio [OR] 1.06, P < 0.05, confidence interval [CI] 95%, 1.005-1.120], and an increased risk of cardiac-related death (OR 1.12, P < 0.05, CI 95% 1.012-1.275). There was no difference in the need for target lesion revascularization among individuals with normal and abnormal GLS (1.00, P 0.88, CI 95% .950-1.061). Left ventricular strain analysis by speckle-tracking echocardiography showed an independent prognostic value in patients with nonrevascularized nonhemodynamically significant coronary lesions.

Transient Ischemic Dilation Ratio in Regadenoson, Single Isotope Gated Single-photon Emission Computed Tomography Myocardial Perfusion Imaging.

Single isotope 99mTc single-photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI) is the most commonly used protocol for nuclear stress testing. Transient ischemic dilation of the left ventricle (TID) has been considered a specific marker of severe coronary artery disease (CAD). Recent publications have questioned the clinical utility of TID, specifically with regadenoson as a stressor and 4DM-SPECT software for TID analysis. These findings have not been demonstrated using other imaging packages. The goal of our study was to establish the TID threshold in the identification of Multi-vessel CAD using Quantitative Perfusion SPECT (QPS) software. Included in this study are 190 patients that had undergone regadenoson-stress, same day, single-isotope 99mTc MPI and had a coronary angiography within a designated 3-month period. QPS (Cedars-Sinai, LA, CA) automated image analysis software was used to calculate TID ratios which were compared across different CAD categories. Coronary angiograms were reviewed to identify both obstructive and nonobstructive CAD. The mean TID for patients with nonobstructive CAD (n = 91) was 1.02 ± 0.11, and the threshold for TID was 1.24. A receiver operating characteristic curve showed that TID had a poor discriminatory capacity to identify MVD (area under the curve 0.58) with a sensitivity of 3% and a specificity of 97%. In our study with regadenoson MPI in a predominantly African-American population, TID was found to be a poor predictor of MVD using QPS software. The reason is unclear but possibly related to the significant decline in the prevalence of severe CAD in the area where our study took place.

Utility of Dobutamine Stress Echocardiography in Cardiac Risk Stratification of Patients Undergoing Orthotopic Liver Transplantation.

Cardiovascular diseases are a major cause of morbidity and mortality in patients after orthotopic liver transplantation (OLT). This review includes major original articles published in the English-language literature of patients who underwent dobutamine stress echocardiography (DSE) before OLT for cardiac risk stratification. Of a total of 10 original articles (total 1699 patients undergoing DSE), 6 studies used DSE to predict major adverse cardiac events (MACE) in patients undergoing OLT and 4 reported the role of DSE in coronary artery disease (CAD) prediction in patients with end-stage liver disease. The composite incidence of MACE was 11.4%. In predicting postoperative MACE, DSE had a composite sensitivity of 0.12 (95% CI, 0.07-0.19), a specificity of 0.96 (95% CI, 0.94-0.97), a positive predictive value (PPV) of 0.26 (95% CI, 0.16-0.38), and a negative predictive value (NPV) of 0.89 (95% CI, 0.88-0.91). The presence of known CAD in a patient was shown to increase the risk of cardiac events after OLT significantly in three of six studies. The average prevalence of CAD was 14.4%. In predicting CAD, DSE had a composite sensitivity of 0.47 (95% CI, 0.32-0.62), specificity of 0.74 (95% CI, 0.68- 0.79), PPV of 0.23 (95% CI, 0.15-0.33), and NPV of 0.89 (95% CI, 0.84-0.93). This review emphasizes the need for standardizing cardiac risk stratification protocol to screen and prevent cardiac morbidity after OLT, standardizing MACE definition to allow more uniform reporting, and the need for safer and efficacious alternatives to DSE in the evaluation of OLT candidates.

Newer modalities for imaging nonischemic cardiomyopathy.

Cardiomyopathies are practically classified as either ischemic or nonischemic based on the presence or absence of coronary artery disease. Although conventional twodimensional echocardiography can assess left ventricular ejection fraction, wall motion, and diastolic function, it does not fully capture myocardial mechanics or tissue characterization, and does not accurately identify patients with nonischemic cardiomyopathy (NICMP) at risk for sudden cardiac death. This article discusses advanced imaging modalities for assessment of NICMP, namely, three-dimensional echocardiography, strain imaging, cardiac magnetic resonance, cardiac computed tomography, and sympathetic innervation imaging.

Therapeutic potentials of phosphodiesterase-5 inhibitors in cardiovascular disease.

Phosphodiesterase-5 (PDE5) inhibitors have been approved by the US Food and Drug Administration for the treatment of erectile dysfunction and more recently for pulmonary arterial hypertension (World Health Organization functional class I). PDE5 inhibitors can induce vasodilation; in addition, through a complex pathway involving nitric oxide, cyclic guanosine monophosphate, and protein kinase G, it can reduce apoptosis and suppress cell proliferation. The presence of PDE5 inhibitors in various tissues and systemic vasculature make them potential targets in a variety of cardiovascular diseases. In many in vitro and in vivo studies, PDE5 inhibitors have been shown to have positive effects in systolic and diastolic congestive heart failure, ischemic heart disease, doxorubicin cardiomyopathy, and pulmonary arterial hypertension. They also improved vasoconstriction in Raynaud phenomenon, peripheral artery disease, and hypoxic brain conditions. This article reviews the therapeutic potentials of PDE5 inhibitors in different cardiovascular diseases.

Incidence, predictors, and outcomes of gastrointestinal bleeding in patients on dual antiplatelet therapy with aspirin and clopidogrel.

OBJECTIVES: The benefits of dual antiplatelet therapy are counterbalanced by the increased incidence of gastrointestinal (GI) complications. The aim of this study was to determine the frequency of GI bleeding, identify the predictors associated with the increased bleeding, and determine the short-term and long-term outcomes. METHODS: This was an observational, case-control cohort study carried out at the Albert Einstein Medical Center. It included all patients who had a drug-eluting stent implanted between May 2003 and April 2007. A total of 1852 patients were identified; of these 50 patients were readmitted for a GI bleed. A control group of 202 patients who did not have any evidence of GI bleeding were compared with the original group. All data were expressed as mean±SD. The baseline clinical characteristics between the 2 groups were compared using the t test and the Fisher exact test. Multivariate analysis was used to determine the predictors of GI bleeding. RESULTS: The rate of GI bleeding was 2.7%. The mean age in the group with GI bleeding was 70.9±12.2 years, whereas in the group without GI bleeding it was 66.5±12.8 years (P<0.05). The majority of the patients presented with melena (40%). Gastritis and gastric ulcers were the most common findings seen in 49% of the patients on endoscopy. On multivariate logistic regression analysis, a history of GI bleeding was the most important independent predictor of future GI bleeding (P<0.001), whereas the use of statins was found to be protective (95% confidence interval, 0.13-0.48; P<0.001) against future GI bleeding. The 30-day mortality rate in the GI bleeding and control groups was 3.7% and 0%, respectively (P<0.01), whereas in the corresponding 1 year the mortality rate was 18.9% and 0%, respectively (P<0.001). CONCLUSIONS: The rate of GI bleeding in patients on dual antiplatelet therapy is low. Earlier history of GI bleeding is the most significant multivariate predictor of future GI bleeding whereas statins seemed to be protective. Patients with GI bleeding have increased short-term and long-term mortality; thereby a history of earlier GI bleeding needs to be assessed carefully before starting dual antiplatelet therapy. This may play a vital role in the selection of therapeutic strategies in these patients.

Heparin-induced thrombocytopenia: a practical review.

Heparin-induced thrombocytopenia (HIT) remains under-recognized despite its potentially devastating outcomes. It begins when heparin exposure stimulates the formation of heparin-platelet factor 4 antibodies, which in turn triggers the release of procoagulant platelet particles. Thrombosis and thrombocytopenia that follow comprise the 2 hallmark traits of HIT, with the former largely responsible for significant vascular complications. The prevalence of HIT varies among several subgroups, with greater incidence in surgical as compared with medical populations. HIT must be acknowledged for its intense predilection for thrombosis and suspected whenever thrombosis occurs after heparin exposure. Early recognition that incorporates the clinical and serologic clues is paramount to timely institution of treatment, as its delay may result in catastrophic outcomes. The treatment of HIT mandates an immediate cessation of all heparin exposure and the institution of an antithrombotic therapy, most commonly using a direct thrombin inhibitor. Current "diagnostic" tests, which primarily include functional and antigenic assays, have more of a confirmatory than diagnostic role in the management of HIT. Special attention must be paid to cardiac patients who are often exposed to heparin multiple times during their course of treatment. Direct thrombin inhibitors are appropriate, evidence-based alternatives to heparin in patients with a history of HIT, who need to undergo percutaneous coronary intervention. As heparin remains one of the most frequently used medications today with potential for HIT with every heparin exposure, a close vigilance of platelet counts must be practiced whenever heparin is initiated.

Infiltrative diseases of the heart.

Infiltrative diseases targeting the cardiovascular system are a subgroup of restrictive cardiomyopathies. An early diagnosis is critical in initiating therapy to mitigate the deleterious effects of the pathologic process underlying these forms of cardiomyopathies. Infiltrative cardiac disease is rare and therefore often underdiagnosed. This review outlines the prevalence of 3 of the most common forms of restrictive cardiomyopathy: sarcoidosis, hemochromatosis, and amyloidosis. Infiltrative cardiomyopathy can have a variable prognosis depending on its etiology. It is a progressive disorder that, if left untreated, can lead to early mortality. A summary of the pathology, diagnosis, disease course, and therapy is provided, along with the utility of noninvasive testing as a means of diagnosis.

Prognostic implications of myocardial perfusion single-photon emission computed tomography in the elderly.

BACKGROUND: The goal of this study was to assess the clinical value of stress myocardial perfusion scintigraphy (MPS) in elderly patients (> or =75 years of age). METHODS AND RESULTS: We followed up 5200 elderly patients (41% exercise) after dual-isotope MPS over 2.8+/-1.7 years (362 cardiac deaths [CDs], 7.0%, 2.6%/y) and a subset with extended follow-up (684 patients for 6.2+/-2.9 years; 320 all-cause deaths). Survival modeling of CD revealed that both MPS-measured ischemia and fixed defect added incrementally to pre-MPS data in both adenosine and exercise stress patients. Modeling a subset with gated MPS (n=2472) revealed that ejection fraction and perfusion data added incrementally to each other, further enhancing risk stratification. Unadjusted, annualized post-normal MPS CD rate was 1.3% but <1% in patients with normal rest ECG, exercise stress, or age of 75 to 84 years and was 2.3% to 3.7% in patients > or =85 years of age or undergoing pharmacological stress. However, compared with age-matched US population CD rates (75 to 84 years of age, 1.5%; > or =85 years, 4.8%), normal MPS CD rates were approximately one-third lower than the baseline risk of US individuals (both P<0.05). Modeling of all-cause death in 684 patients with extended follow-up revealed that after risk adjustment, an interaction between early treatment and ischemia was present; increasing ischemia was associated with increasing survival with early revascularization, whereas in the setting of little or no ischemia, medical therapy had improved outcomes. CONCLUSIONS: Stress MPS effectively stratifies CD risk in elderly patients and may identify optimal post-MPS therapy. CD rates after normal MPS are low in all subsets in relative terms compared with the age-matched US population.

Acute aortic syndromes: pathophysiology and management.

The acute aortic syndromes carry significant morbidity and mortality, especially when detected late. Symptoms may mimic myocardial ischemia, and physical findings may be absent or, if present, can be suggestive of a diverse range of other conditions. Maintaining a high clinical index of suspicion is crucial in establishing the diagnosis. All patients with suspected aortic disease and evidence of acute ischemia on electrocardiogram should undergo diagnostic imaging studies before thrombolytics are administered. The demonstration of an intimal flap separating 2 lumina is the basis for diagnosis. Tear detection and localization are very important because any therapeutic intervention aims to occlude the entry tear. The goals of medical therapy are to reduce the force of left ventricular contractions, decrease the steepness of the rise of the aortic pulse wave, and reduce the systemic arterial pressure to as low a level as possible without compromising perfusion of vital organs. Surgical therapy still remains the gold standard of care for type A aortic dissection, whereas in type B dissection, percutaneous aortic stenting and fenestration techniques have been developed and are sometimes used in conjunction with medical therapy in certain situations.

Evaluation of anomalous aortic origins of the coronaries by 64-slice cardiac computed tomography.

Approximately 20% of coronary artery anomalies produce sudden death or life-threatening symptoms, including arrhythmias, syncope, and myocardial infarction. The most common clinical symptom of coronary artery anomaly is angina or exertional syncope. Physical examination is usually unrevealing in the absence of myocardial infarction or symptoms of ongoing ischemia. The rapid advent of cardiac computed tomography (CT) technology has made it an important adjunct to the diagnosis of coronary anomalies by angiography. The authors describe the case of a 54-year-old white man who presented with gangrenous toes. He had severe peripheral vascular disease, a femoral-popliteal bypass graft, residual hemiparesis from an ischemic stroke, hypertension, deep vein thrombosis, and a recent myocardial infarction. He underwent a 64-slice cardiac CT angiogram, which showed an interarterial course of the left main coronary artery between the aorta and the pulmonary trunk.

Acute myocardial infarction in a patient with systemic lupus erythematosus and normal coronary arteries.

Although cardiac manifestations such as pericardial, myocardial, and valvular involvement are common in patients with systemic lupus erythematosus (SLE), coronary artery involvement is less frequent. Clinical manifestations of coronary artery disease in SLE can result from accelerated atherosclerosis, arteritis, abnormal coronary flow reserve, spasm, and thrombosis. In SLE, the classic valvular abnormality consists of noninfective, verrucous vegetation. Thickening of the leaflets due to inflammation followed by fibrosis is common, occurring in about 50% of patients, whereas vegetations are present in about 40%. Mitral valve involvement is most common, with valvular regurgitation more frequent than valvular stenosis. The tricuspid valve and the aortic valve may also be affected. Its frequency varies widely: 13% to 74% in the general population. We report a case of a woman with acute myocardial infarction and normal coronary arteries, who was subsequently diagnosed with Libman-Sacks endocarditis and SLE.

Differentiating constrictive pericarditis from restrictive cardiomyopathy.

Constrictive pericarditis and restrictive cardiomyopathy are 2 forms of diastolic dysfunction with similar presentation but different treatment options. Whereas constrictive pericarditis has the potential of being cured with pericardiectomy, restrictive cardiomyopathy is usually incurable. It is therefore crucial to differentiate between the 2 disorders. In the last few years, new diagnostic techniques have become available to differentiate these causes of diastolic dysfunction from each other. This review provides a complete, in-depth comparison of the 2 disorders with regard to their symptoms and clinical features, etiology, pathophysiology, hemodynamics, echocardiographic presentation, and finally the different available management options.

Adenosine myocardial perfusion single-photon emission computed tomography in women compared with men. Impact of diabetes mellitus on incremental prognostic value and effect on patient management.

OBJECTIVES: This study was designed to assess the incremental prognostic value of adenosine stress myocardial perfusion single-photon emission computed tomography (MPS) in women versus men, and to explore the prognostic impact of diabetes mellitus. BACKGROUND: Limited data are available regarding the incremental value of adenosine stress MPS for the prediction of cardiac death in women versus men and the impact of diabetes mellitus on post-adenosine MPS outcomes. Of 6,173 consecutive patients who underwent rest thallium-201/adenosine technetium-99m sestamibi MPS, 254 (4.1%) were lost to follow-up, and 586 with early revascularization < or = 60 days after MPS were censored, leaving 2,656 women and 2,677 men. RESULTS: Women had significantly smaller adenosine stress, rest, and reversible defects than men. During 27.0 +/- 8.8 month follow-up, cardiac death rates were lower in women than men (2.0%/year vs. 2.7%/year, respectively, p < 0.05). Before and after risk adjustment, cardiac death risk increased significantly in both men and women as a function of MPS results. Multivariable models revealed that MPS results provided incremental prognostic value over pre-scan data for the prediction of cardiac death in both genders. Also, while comparative unadjusted rates of early (< or =60 days post-test) coronary angiography (17% vs. 23%) and revascularization (8% vs. 12%) were significantly lower in women (p < 0.05), after adjusting for MPS, these rates were similar in men and women. Importantly, diabetic women had a significantly greater risk of cardiac death compared with other patients. Also, after risk adjustment, patients with insulin-dependent diabetes mellitus (IDDM) had higher risk of cardiac death for any MPS result than patients with non-insulin-dependent diabetes mellitus. CONCLUSION: The findings suggest that adenosine MPS has comparable incremental value for prediction of cardiac death in women and men and that MPS is appropriately influencing subsequent invasive management decisions in both genders. Diabetic women and patients with IDDM appear to have greater risk of cardiac death than other patients for any MPS result.

Risk stratification in patients with remote prior myocardial infarction using rest-stress myocardial perfusion SPECT: prognostic value and impact on referral to early catheterization.

BACKGROUND: Little is known about the prognostic value of myocardial perfusion single photon emission computed tomography (SPECT) in patients with remote prior myocardial infarction (MI). METHODS AND RESULTS: We identified 1413 consecutive patients with remote prior MI who underwent rest-stress myocardial perfusion SPECT. Semiquantitative visual analysis of 20 SPECT segments was used to define the summed stress, rest, and difference scores. The number of non-reversible segments was used as an index of infarct size. During follow-up (>or=1 year), 118 hard events occurred: 64 cardiac deaths (CDs) and 54 recurrent MIs. Annual CD and hard event rates increased significantly as a function of SPECT abnormality. For summed stress scores less than 4, 4 to 8, 9 to 13, and more than 13, the annual CD rates were 0.4%, 0.9%, 1.7%, and 3.5%, respectively (P =.002). Patients with small MI (<4 non-reversible segments) and no or mild ischemia (summed difference score or=4 non-reversible segments) had moderate to high annual CD rates (3.7%-6.6%) regardless of the extent of ischemia. Nuclear testing added incremental prognostic information to pre-scan information. Compared with a strategy in which all patients are referred to catheterization, a strategy that referred only those patients with a risk for CD of greater than 1% by myocardial perfusion SPECT resulted in a 41.6% cost savings. CONCLUSIONS: Myocardial perfusion SPECT adds incremental value to pre-scan information and is highly predictive and cost-efficient in the risk stratification of patients with remote prior MI. Patients with normal or mildly abnormal scan results or small MI in combination with absent or mild ischemia have a low risk for CD.