A Reminder That Stress Echocardiography Is Useful in Diagnosing Myocardial Ischemia in Nonobstructive Coronary Artery Disease: Case Series.

Identification of ischemia remains critical when assessing individuals presenting with atypical symptoms or in patients with known coronary artery disease (CAD). Several imaging modalities are currently available to attain this diagnostic goal. Unfortunately, not all case presentations are straightforward, particularly when microvascular dysfunction (MVD) is the cause of symptoms in the absence of identifiable epicardial luminal stenosis. Specifically, in such cases, current imaging guidelines do not include stress echocardiography (SE) as a recommended tool when assessing these patients. We present three cases that highlight the utility of SE for identifying MVD and provide mechanistic explanations. We believe that SE should not be completely discarded as an inadequate testing modality; we highlight the potential utility of this imaging modality not only in diagnosing CAD and pre-surgical evaluation of patients but also in identifying patients with MVD.

Tilting of the Cardiac Axis During Dobutamine Stress Echocardiography: Potential Marker for Ischemia.

Stress echocardiography is a tool for assessing the extent and severity of coronary artery disease (CAD) during physical or pharmacological stress. Transient worsening of regional left ventricular (LV) function during stress is a well-recognized abnormality of inducible ischemia. We present the case of a 57-year-old female with risk factors for CAD who was referred for a dobutamine stress echocardiogram for complaints of typical angina. It was interpreted as positive for inducible ischemia, but using unconventional criteria. Unfortunately, this study had reduced sensitivity due to LV hypertrophy. All LV wall segments were not clearly seen to comment on regional contractility, and an abnormal cardiac tilt from its axis was noted, suggestive of ischemia along the anteroseptal, anterior and lateral walls. Following this, a coronary angiogram showed diffuse CAD. The cardiac axis with the presence of a tilt as a potential measure of ischemia is previously unrecognized. The idea invokes a mathematical principle based on the direction and the magnitude of the vector of opposing walls during contractility. Simply implying that ischemic segments might contract in the same direction, vector magnitude will be less prominent; hence, "axial tilt" will occur. Prospective studies are needed to validate the feasibility and reproducibility of this abnormality in the assessment of ischemia and its viability in clinical practice.

Recurrent ST Elevation Myocardial Infarction from Norepinephrine-induced Coronary Vasospasm.

Myocardial infarction with no obstructive coronary atherosclerosis (MINOCA) is a distinct clinical syndrome characterized by evidence of myocardial infarction with normal or near-normal coronary arteries on angiography (stenosis severity < 50%). Coronary artery spasm, as seen in "variant angina," usually occurs at a localized segment of an epicardial artery. Here, we present a case of a 58-year-old male who had norepinephrine-induced coronary vasospasm which resulted in ST elevation myocardial infarction on two consecutive admissions.

Ruptured Sinus of Valsalva Aneurysm Causing Aorto-Atrial Fistula and Acute Heart Failure: A Rare Encounter.

A ruptured sinus of Valsalva aneurysm as a cause of aorto-atrial fistula is very rare. We present the case of a 53-year-old female who presented with symptoms of acute heart failure and suspicion of an aorto-atrial fistula found on a transthoracic echocardiogram, which was confirmed on transesophageal echocardiography. A coronary angiogram showed normal coronary arteries but confirmed the right aorto-atrial fistula on aortogram. She underwent successful surgical repair of the fistula. Her postoperative echocardiogram showed a normal right atrium and right ventricle with no shunt. A ruptured sinus of Valsalva aneurysm is a devastating event and presents as acute heart failure. Prompt diagnosis and surgical repair is necessary to prevent mortality. LEARNING POINTS: A ruptured sinus of Valsalva aneurysm causing an aorto-atrial fistula can present as acute heart failure.A transthoracic echocardiogram can identify the presence and location of a sinus of Valsalva aneurysm, while a transesophageal echocardiogram can recognize fistulous tract formation. Cardiac magnetic resonance imaging and computed tomography can confirm or better categorize echocardiographic findings.The management of an aorto-atrial fistula is surgical intervention, involving a patch repair.

Vasopressor-Induced Generalized Coronary Vasospasm Presenting as Inferior ST-Segment Elevation in Post-Cardiopulmonary Resuscitation.

ST-segment elevation in post-return of spontaneous circulation after cardiac arrest is a major concern for underlying acute coronary syndrome. This case report presents a rare case of vasopressor-induced coronary vasospasm as an underlying cause for this ST-segment elevation with complete reversal of EKG changes after reducing the vasopressor dose. (Level of Difficulty: Beginner.).

Three-dimensional transesophageal echocardiography is an attractive alternative to cardiac multi-detector computed tomography for aortic annular sizing: Systematic review and meta-analysis.

BACKGROUND: Cardiac imaging is the cornerstone of the pretranscatheter aortic valve replacement (TAVR) assessment. Multi-detector computed tomography (MDCT) is considered the conventional imaging modality. However, there is still no definitive gold standard. Targeted cohort of inoperable high-risk patients with underlying comorbidities, particularly renal impairment, makes apparent the need for MDCT alternative. We aimed to demonstrate the correlation extent between MDCT and three-dimensional transesophageal echocardiography (3DTEE) aortic annular area measures and to answer the question: Is 3DTEE a good alternative to MDCT? METHODS: A systematic literature search and meta-analysis were conducted to evaluate the degree of correlation and agreement between 3DTEE and MDCT aortic annular sizing. A thorough assessment of EMBASE, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL) was performed. All studies comparing 3DTEE and MDCT in relation to aortic annular sizing were included. RESULTS: Thirteen studies were included (N = 1228 patients). A strong linear correlation was found between 3DTEE and MDCT measurements of aortic annulus area (r = 0.84, P < 0.001), mean perimeter (r = 0. 0.85, P < 0.001), and mean diameter (r = 0.80, P < 0.001). Bland-Altman plots revealed smaller mean 3DTEE values in comparison to MDCT for aortic annular area, the mean difference being -2.22 mm2 with 95% limits of agreement -12.79 to 8.36. CONCLUSION: Aortic annulus measurements obtained by 3DTEE demonstrated a high level of correlation with those evaluated by MDCT. This makes 3DTEE a feasible choice for aortic annulus assessment, with advantage of real time assessment, lack of contrast, and no radiation exposure.

Comparison of the Frequency of Acute Kidney Injury in Patients With Renal Transplant Who Underwent Percutaneous Coronary Intervention Versus Coronary Artery Bypass Graft Surgery.

Percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) are established modalities of coronary revascularization. Choosing between the two requires taking into consideration not only disease severity, patient characteristics, and expected outcomes but also adverse effects. One such adverse effect is acute kidney injury (AKI), especially when considering coronary revascularization in patients with renal transplant (RT). We searched the National Inpatient Sample from 2008 to 2014 using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for patients with RT (V42.0) who underwent PCI (00.66, 36.06, and 36.07) and CABG (36.1×, 36.2, and 36.3×). We further identified patients with AKI (584.5, 584.6, 584.7, 584.8, and 584.9) and those on dialysis (39.95). The propensity score model/method was used to form matched cohorts for PCI and CABG. We compared the incidence of AKI and AKI requiring dialysis in CABG and PCI groups. We identified 1,871 patients who underwent PCI and 1,878 patients who underwent CABG after propensity score matching. We found the incidence of both AKI (22% vs 38%, odds ratio 2.20, 95% confidence interval 1.91 to 2.54, p <0.0001) and AKI requiring dialysis (1% vs 3%, odds ratio 2.50, 95% confidence interval 1.49 to 4.19, p = 0.001) to be significantly higher in the CABG compared with the PCI cohort. In conclusion, the results of the study reflect the importance of accounting for the RT status before choosing between PCI and CABG for coronary revascularization.

Takotsubo cardiomyopathy secondary to spontaneous right-sided pneumothorax.

Takotsubo cardiomyopathy (TCM) is a unique type of cardiomyopathy characterised by left ventricular systolic dysfunction in association with stressful conditions. Patients with this condition usually present with chest pain and dyspnoea, and the presentation can mimic acute coronary syndrome. We present a case of a woman aged 58 years who presented with progressive dyspnoea and cough. Her initial evaluation was suggestive of acute myocardial infarction with elevated serum troponin T and ST segment elevation. Her chest radiograph showed a large right-sided pneumothorax, which was treated with chest tube insertion. Coronary angiography and echocardiogram did not show any evidence of obstructive coronary artery disease but did show a large area of akinesis consistent with TCM. The patient was managed medically with supportive care. Her pneumothorax resolved, and her follow-up echocardiogram also showed improvement. The association between pneumothorax and TCM is rare, and only four other cases have been reported so far in the English literature.

Predicting long-term bleeding after percutaneous coronary intervention.

OBJECTIVES: To construct a model to predict long-term bleeding events following percutaneous coronary intervention (PCI). BACKGROUND: Treatment with dual antiplatelet therapy following PCI involves balancing the benefits of preventing ischemic events with the risks of bleeding. There are no models to predict long-term bleeding events after PCI. METHODS: We analyzed 1-year bleeding outcomes from 3,128 PCI procedures in the Patient Risk Information Services Manager (PRISM) observational study. Patient-reported bleeding events were categorized according to Bleeding Academic Research Consortium (BARC) definitions. Logistic regression analysis was used to develop a model predicting BARC ≥ 1 bleeding. RESULTS: BARC 0, 1, 2 or 3 bleeding was observed in 574 (18.4%); 2382 (76.2%); 114 (3.6%); and 58 (1.8%) patients, respectively. Compared to patients who had no bleeding, patients with BARC ≥ 1 bleeding were more often female (30 vs. 23%), Caucasian (94 vs. 83%), had a higher incidence of drug eluting stent (DES) implantation (83 vs. 76%) and warfarin therapy (7.4 vs. 3.9%), and a lower incidence of diabetes (31 vs. 45%; P-value <0.01 for all comparisons). A 27-variable model had moderate discrimination (c-statistic of 0.674), and good calibration, as did a parsimonious model with 10 variables (c-statistic = 0.667). This model performed well in predicting BARC ≥ 2 bleeding events as well (c-statistic = 0.653). CONCLUSIONS: Bleeding is common in the first year after PCI, and can be predicted by pre-procedural patient characteristics and use of DES. Objective estimates of bleeding risk may help support shared decision-making with respect to stent selection and duration of antiplatelet therapy following PCI. © 2016 Wiley Periodicals, Inc.

Pulmonary vein thrombosis in a patient with polycythemia vera.

Pulmonary vein thrombosis (PVT) is a rarely encountered disease entity with varied clinical presentations. It is usually associated with lung carcinoma, lung surgeries and as a complication of the radiofrequency catheter ablation procedure for atrial fibrillation. Its clinical manifestations can vary from mild hemoptysis to lung infarction with hemodynamic compromise. A 76-year-old male presented with a 2-d history of pleuritic left sided chest pain. His past medical history included polycythemia vera, atrial fibrillation, coronary artery disease, pulmonary embolism and pulmonary hypertension. Chest radiograph was normal, troponins were normal and the 12-lead electrocardiogram did not show any ischemic changes. A computerized tomography pulmonary angiogram revealed a filling defect in the left lower lobe pulmonary vein. He was treated with subcutaneous enoxaparin and his symptoms improved. This case highlights a rare etiology of chest pain and the first reported case of the association of polycythemia vera and pulmonary vein thrombosis. A high index of suspicion is required for appropriate diagnostic work up. PVT can mimic pulmonary embolism. The diagnostic work up and treatment strategies depend on acuity of presentation.

Refractory ventricular fibrillation managed by coronary revascularisation performed during ongoing manual cardiac resuscitation lasting 1½ h.

Myocardial infarction is the most common cause of ventricular arrhythmias. Although there have been several improvements and refinements in coronary catheterisation with percutaneous intervention over the years, this intervention is still rarely considered during active ongoing resuscitation of patients, especially in cases of persistent ventricular arrhythmias. We present a case of refractory ventricular fibrillations due to in-stent thrombosis that was managed by emergent coronary angiogram and stent placement during ongoing cardiopulmonary resuscitation in a code that lasted about 1½ h. The patient subsequently made an excellent recovery and was discharged home 13 days later.

Asymptomatic coronary artery disease in type II diabetes.

Coronary artery disease is a major cause of morbidity and mortality in patients with diabetes mellitus and remains one of the largest burdens on health care resources. Prevalence of asymptomatic CAD in this population is high and poses a diagnostic challenge due to lack of overt clinical complaints. At this time there is no clear algorithm to screen for silent myocardial ischemia in diabetics. In this article we review various diagnostic tools available for assessment and propose a step wise approach for risk stratification in these patients.

Creatine kinase-MB: the journey to obsolescence.

OBJECTIVES: To evaluate the clinical utility of and demand for the creatine kinase (CK)-MB assay. METHODS: We examined the number of CK-MB tests from 2007 through 2013 while we progressively deemphasized their use. We first removed CK-MB from the acute coronary syndrome (ACS) panel and then from the main menu and observed the demand for the test. We also reviewed patient medical records to assess the appropriateness of its use. RESULTS: After removing CK-MB from the ACS panel, the test volume dropped from around 12,000 per year to about 150 per year. In reviewing the records of 171 patients who had CK-MB determination done over a 28-month period, we discovered that CK-MB contributed to the diagnosis in only one patient, although it was not essential. Since removing CK-MB from the laboratory menu, two CK-MB tests were ordered in 4 months, and neither added value. CONCLUSIONS: CK-MB determinations do not add value to information available from the troponin assay and can be safely removed from the laboratory menu.

Obesity: the 'huge' problem in cardiovascular diseases.

Obesity is an epidemic in the United States. It is an independent risk factor for cardiovascular diseases and associated with reduced life expectancy. The adverse effects are related to direct impact of obesity on cardiovascular system and indirectly through its influence on risk factors. Excessive accumulation of adipose tissue in the myocardium leads to structural and functional alteration. In addition, numerous hormones secreted by adipose tissue create pro-inflammatory and prothrombotic state. This predisposes to coronary heart disease, heart failure, and sudden death. Even those with normal weight but excessive body fat are at risk. Weight reduction and exercise are the main therapeutic options.

Water immersion-induced skin wrinkling is related to heart rate variability.

Water immersion-induced skin wrinkling (WISW) is dependent on intact peripheral sympathetic function. WISW was hypothesized to reflect autonomic function in subjects without peripheral neuropathy. We prospectively studied 70 healthy subjects (aged 31 ± 8 years, 63% females) without cardiovascular risk factors or neurological disease. All subjects underwent short-term heart rate variability (HRV) studies. Time and frequency domain variables were derived including the HRV index. WISW was graded using a previously validated scale of 1-4 of which 18.6% of subjects exhibited grade 1 (minimal) WISW and 35.7% had grade 2 WISW. On multivariate analysis using the HRV index, WISW was independently related to height and the HRV index. We conclude that WISW is related to central autonomic function.

The kinetics of spontaneous calcium oscillations and arrhythmogenesis in the in vivo heart during ischemia/reperfusion.

BACKGROUND: The correlation between spontaneous calcium oscillations (S-CaOs) and arrhythmogenesis has been investigated in a number of theoretical and experimental in vitro models. There is an obvious lack of studies that directly investigate how the kinetics of S-CaOs correlates with a specific arrhythmia in the in vivo heart. OBJECTIVES: The purpose of the study is to investigate the correlation between the kinetics of S-CaOs and arrhythmogenesis in the intact heart using an experimental model of ischemia/reperfusion (I/R). METHODS: Perfused Langendorff guinea pig (GP) hearts were subjected to global I/R (10-15 minutes/10-15 minutes). The heart was stained with a voltage-sensitive dye (RH237) and loaded with a Ca2+ indicator (Rhod-2 AM). Membrane voltage (Vm) and intracellular calcium transient (Ca(i)T) were simultaneously recorded with an optical mapping system of two 16 x 16 photodiode arrays. S-CaOs were considered to arise from a localized focal site within the mapped surface when these preceded the associated membrane depolarizations by 2-15 ms. RESULTS: In 135 episodes of ventricular arrhythmias from 28 different GP experiments, 23 were linked to S-CaOs that were considered to arise from or close to the mapped epicardial window. Self-limited or sustained S-CaOs had a cycle length of 130-430 ms and could trigger propagated ventricular depolarizations. Self-limited S-CaOs that followed the basic beat action potential (AP)/Ca(i)T closely resembled phase 3 early afterdepolarizations. Fast S-CaOs could remain confined to a localized site (concealed) or exhibit varying conduction patterns. This could manifest as (1) an isolated premature beat (PB), bigeminal, or trigeminal rhythm; (2) ventricular tachycardia (VT) when a regular 2:1 conduction from the focal site develops; or (3) ventricular fibrillation (VF) when a complex conduction pattern results in wave break and reentrant excitation. CONCLUSIONS: The study examined, for the first time in the intact heart, the correlation between the kinetics of focal S-CaOs during I/R and arrhythmogenesis. S-CaOs may remain concealed or manifest as PBs, VT, or VF. A "benign looking" PB during I/R may represent "the tip of the iceberg" of an underlying potentially serious arrhythmic mechanism.

Contrasting effects of ischemia on the kinetics of membrane voltage and intracellular calcium transient underlie electrical alternans.

Repolarization alternans has been considered a strong marker of electrical instability. The objective of this study was to investigate the hypothesis that ischemia-induced contrasting effects on the kinetics of membrane voltage and intracellular calcium transient (Ca(i)T) can explain the vulnerability of the ischemic heart to repolarization alternans. Ischemia-induced changes in action potential (AP) and Ca(i)T resulting in alternans were investigated in perfused Langendorff guinea pig hearts subjected to 10-15 min of global no-flow ischemia followed by 10-15 min of reperfusion. The heart was stained with 100 microl of rhod-2 AM and 25 microl of RH-237, and AP and Ca(i)T were simultaneously recorded with an optical mapping system of two 16 x 16 photodiode arrays. Ischemia was associated with shortening of AP duration (D) but delayed upstroke, broadening of peak, and slowed decay of Ca(i)T resulting in a significant increase of Ca(i)T-D. The changes in APD were spatially heterogeneous in contrast to a more spatially homogeneous lengthening of Ca(i)T-D. Ca(i)T alternans could be consistently induced with the introduction of a shorter cycle when the upstroke of the AP occurred before complete relaxation of the previous Ca(i)T and generated a reduced Ca(i)T. However, alternans of Ca(i)T was not necessarily associated with alternans of APD, and this was correlated with the degree of spatially heterogeneous shortening of APD. Sites with less shortening of APD developed alternans of both Ca(i)T and APD, whereas sites with greater shortening of APD could develop a similar degree of Ca(i)T alternans but slight or no APD alternans. This resulted in significant spatial dispersion of APD. The study shows that the contrasting effects of ischemia on the duration of AP and Ca(i)T and, in particular, on their spatial distribution explain the vulnerability of ischemic heart to alternans and the increased dispersion of repolarization during alternans.