Myocardial Perfusion Stress Test Research Articles

Abstract 11581: False Positive Troponin Elevation Due to Heterophile Antibody

Introduction: While highly specific, false positive Troponin I (TnI) can be caused by heterophile antibodies, autoimmune phenomena, and fibrin interference. The overreliance on TnI levels can lead to unnecessary patient work-up. Here we present a case of chronically elevated troponin over several hospitalizations most consistent with viral heterophile antibody cross reactivity. Case: A 71-year-old man with diabetes and polio-related paraplegia was admitted for pharyngitis. Initial TnI assay was significantly elevated at >90 (normal < 0.04 ng/mL) with a CK-MB of 21.7 (normal <20.0 U/L). ECG showed no evidence of ischemia (Figure 1). He had similar TnI elevation on two prior hospitalizations, with no significant coronary artery disease on angiography. Despite the absence of chest pain and normal ECG and TTE, myocardial perfusion stress test was performed due to the elevation in CK-MB, which was negative for ischemia (Figure 2). Troponin T, a sendout lab, was <12 ng/L. Patient was later confirmed to have positive CMV IgG and positive EBV viral capsid and nuclear antigen IgG, supporting the mechanism of heterophile antibody cross reactivity as the mechanism for false positive troponin. Discussion: Our case demonstrates a growing literature of patients presenting with chronically elevated TnI unrelated to myocyte damage. Focus of troponin levels without consideration of overall clinical picture and previous medical history can lead to unnecessarily invasive and expensive testing. For this patient, elevated troponin led to unnecessary testing and prolonged hospital admissions despite consistently negative cardiac workup. Heterophile cross reactivity can lead to false positive TnI in 1:2000 patients. If elevated troponin is concerning for a false positive, evaluation through other markers should be considered before undergoing more invasive procedures.

Angiographic and Clinical Predictors of Mild Non-Culprit Coronary Lesion Progression in Acute ST-Elevation Myocardial Infarction Managed by Primary Percutaneous Coronary Intervention: A Prospective Cohort Study

Abstract Aims To identify the angiographic and clinical predictors of mild non-culprit coronary lesion (NCCL) progression in acute ST-elevation myocardial Infarction (STEMI). Methods and Results The present prospective cohort study evaluated 200 patients with acute STEMI underwent primary percutaneous coronary intervention (PPCI) (either PPCI or pharmaco-invasive PCI) divided into2groups based on whether the clinically driven non culprit lesion PCI existed or not into: Control group-1: 157 patients(78.5%) with non-progressed non culprit lesion (no additional PCI to the non-culprit lesion) and Study group-2: 43 patients(21.5%) with clinically driven non culprit lesion PCI (underwent additional PCI to progressed non-culprit lesions). Our study end point was the clinically driven non culprit lesion PCI (additional PCI to progressed non-culprit lesions). Asymptomatic patients were followed up by exercise ECG at 12 months and myocardial perfusion stress testing at 24 months. Multivariate regression analysis showed that the strongest independent predictor for progression of mild NCCL was complex morphology of culprit lesion (p < 0.001). Finally, a receiver operating characteristic (ROC) curve was performed to assess a cutoff value for predictors for NCCL progression after PPCI in Patients with STEMI. Conclusions Our novel angiographic independent predictor was complex morphology of culprit lesion. And our novel clinical independent predictors were CRP cutoff more than 7.05mg/l, peak cardiac troponin I value cutoff more than 27.5 ng/ml, and age cutoff less than 57.5 years, could be used for early prediction of mild NCCL progression after PPCI for acute STEMI patients. This could be used for early diagnosis to avoid repeated PCI and proper management for better outcomes.

Cost-effectiveness of myocardial perfusion SPECT and stress test according to coronary revascularization therapy, cardiac events and total mortality: Register of 8496 patients

ObjectiveThe aim was to analyze the cost-effectiveness ratio (CER) of stress electrocardiogram (ES) and stress myocardial perfusion imaging (SPECT-MPI) according to coronary revascularization (CR) therapy, cardiac events (CE) and total mortality (TM). Material and methodsA total of 8496 consecutive patients who underwent SPECT-MPI were followed-up (mean 5.3±3.5 years). Cost-effectiveness for coronary bypass (CABG) or percutaneous CR (PCR) (45.6%/54.4%) according to combined electrocardiographic ischemia and scintigraphic ischemia were evaluated. Effectiveness was evaluated as TM, CE, life-year saved observed (LYSO) and CE-LYSO; costs analyses were conducted from the perspective of the health care payer. A sensitivity analysis was performed considering current CABG/PCR ratios (12%/88%). ResultsWhen electrocardiogram and SPECT approaches are combined, the cost-effectiveness values for CABG ranged between 112,589€ (electrocardiographic and scintigraphic ischemia) and 2,814,715€ (without ischemia)/event avoided, 38,664 and 2,221,559€/LYSO; for PCR ranged between 18,824€ (electrocardiographic and scintigraphic ischemia) and 46,377€ (without ischemia)/event avoided, 6464 and 36,604€/LYSO. To CE: the cost-effectiveness values of the CABG and CPR in presence of electrocardiographic and scintigraphic ischemia were 269,904€/CE-avoided and 24,428€/CE-avoided, respectively; and the €/LYSO of the CABG and PCR were 152,488 and 13,801, respectively. The RCE was maintained for the current proportion of revascularized patients (12%/88%). ConclusionsCombined ES and SPECT-MPI results, allows differentiation between patient groups, where the PCR and CABG are more cost-effective in different economic frameworks. The major CER in relation to CR, CE and TM occurs in patients with electrocardiographic and scintigraphic ischemia. PCR is more cost-effective than CABG.

IRON OVERLOAD CARDIOMYOPATHY PRESENTING AFTER LIVER TRANSPLANTATION

Iron overload cardiomyopathy (IOC) describes different forms of cardiac dysfunction secondary to myocardial iron deposition. A 49 year old female with end-stage alcoholic cirrhosis was referred for transplant evaluation. Pre-operatively, her LVEF was 60-65% and her myocardial perfusion stress test

Stop Being So Sensitive: An Exceptionally Rare Report of Ustekinumab-Induced Sub-acute Hypersensitivity Pneumonitis

Hypersensitivity pneumonitis (HSP) is a rare syndrome characterised by granulomatous inflammatory lung disease due to repeated sensitisation from a specific antigen. We present the case of a 61-year old male veteran with a history of nodular eczema who presented with 2 weeks of progressive dyspnoea on exertion and pleuritic chest pain. The patient was started on ustekinumab 5 weeks prior to presentation. Initial workup revealed ground-glass opacities on computed tomography (CT) scan of the chest. Cardiac workup was unrevealing with a normal myocardial perfusion stress test. The patient was started on inhaled corticosteroids and albuterol for reactive airway disease. Due to the persistence of symptoms despite treatment, the patient underwent bronchoscopy with bronchoalveolar lavage (BAL), transbronchial biopsy and endobronchial ultrasound-guided biopsy (EBUS). Bronchoscopy showed normal appearing airways of both right and left lungs. The BAL was remarkable for chronic inflammation and pulmonary macrophages. The BAL cell count differential was 1% granulocytes, 50% lymphocytes, 17% eosinophils and 32 mononuclear cells. The pathology from the mediastinal lymph nodes showed reactive inflammatory cells and no malignancy. The pathology from the transbronchial biopsy of the anterior basilar segment of the right lower lobe showed organising pneumonia with occasional ill-defined granulomas that stained negative for Acid Fast Bacilli (AFB) and Grocott's methenamine (GMS) appeared to be consistent with hypersensitivity pneumonitis. Based on the pathological diagnosis of HSP, the patient was managed with discontinuation of ustekinumab, with subsequent improvement of his symptoms. To our knowledge, this is the first report suggesting ustekinumab, like other biological therapies, has the potential to cause HSP.

Guidelines and Implications for Selecting Preoperative Cardiac Stress Tests

Nurse practitioners frequently manage patients who have cardiac risks and need further evaluation before their elective surgery. Cardiac stress testing can provide important needed data. Cardiac stress testing includes exercise treadmill testing; echocardiography, with exercise or pharmacologically; myocardial perfusion stress testing; and magnetic resonance angiography. Although a number of factors need to be considered, including prior cardiovascular history and type of surgical risk, a nurse practitioner’s selection of the appropriate cardiac stress test needs to include the benefit-risk ratio and the level of evidence supporting the clinical decision-making process.

The influence of clopidogrel on ischemia diagnosed by myocardial perfusion stress testing

BackgroundClopidogrel is a platelet adenosine receptor antagonist which can influence coronary vascular tone and thus can potentially interfere with myocardial perfusion imaging. We investigated whether clopidogrel can hamper the diagnosis of ischemia in patients undergoing myocardial perfusion testing. MethodsData from a database of 6349 myocardial perfusion stress tests were analyzed. Using a propensity analysis, patients who were taking clopidogrel were compared with patients not taking clopidogrel for the presence of reversible perfusion defects on myocardial single-photon emission computed tomography scans. ResultsOf the 6349 tests, the stress technique was adenosine in 2713 patients and exercise in 3636. At the time of the stress test, 277 (4.3%) of the patients were taking clopidogrel. The odds ratio (OR) for patients taking clopidogrel to have a reversible perfusion defect was 2.75 (95% confidence interval [CI] 2.09-3.62; P < .01). After adjusting for the propensity to take clopidogrel, the OR was 1.06 (CI 0.76-1.49; P = .73) for patients undergoing adenosine stress tests and 1.60 (CI 0.85-3.00; P = .14) for patients undergoing exercise stress tests. ConclusionsWe found no evidence that the use of clopidogrel decreases the likelihood of ischemia on adenosine or exercise stress myocardial perfusion scans.

Hypertrophic Obstructive Cardiomyopathy Diagnosed During Regadenoson Stress Test

Regadenoson (REG) is a selective adenosine A2a receptor agonist which is used as an agent to induce vasodilation for the nuclear myocardial perfusion stress test in patients with suspected coronary artery disease (1). Here we report a case where REG infusion caused immediate accentuation of a murmur with an increase in the left ventricular outflow tract (LVOT) gradient, which led to the diagnosis of hypertrophic obstructive cardiomyopathy (HOCM) in this patient.

Anomalous left main coronary artery originating from the pulmonary artery

An 81 year-old Caucasian female presented to the hospital with dyspnea on exertion and was found to be in new onset atrial fibrillation. She has a past medical history of hypertension and has led an active life till her symptoms of dyspnea started. An echocardiogram was performed as a part of the work up showing an ejection fraction of 35 % with moderate mitral valve regurgitation (Fig. 2). Given her new onset cardiomyopathy and reluctance to undergo invasive work up, a pharmacologic nuclear myocardial perfusion stress test was performed showing a moderate sized area of anterolateral wall mixed ischemia and scar with an ejection fraction of 36 % (Fig. 3). A coronary angiography was recommended but patient was still reluctant and preferred a non-invasive work-up. Thus, a cardiac CT angiography was recommended. This showed an anomalous left main coronary artery originating from the proximal main pulmonary artery just beyond the pulmonic valve. The contrast density in the left main coronary artery is slightly higher than in the pulmonary artery and matches the contrast density in the arterial circulation indicating collateral filling of the left coronary system from either the aorta or right coronary artery (Fig. 4). She was started on beta-blockers and lisinopril. She underwent a successful electrical cardioversion preceded by a transesophageal echocardiogram to rule out left atrial appendage clot. She was started and warfarin and discharged. On follow-up 3 months later, she remained in sinus rhythm with significant improvement in her symptoms. A repeated echocardiogram showed significant improvement in the left ventricular ejection fraction to 55 % with only mild mitral regurgitation. On six-month follow-up she remained asymptomatic with improved functional capacity.

Hybrid myocardial imaging for risk stratification prior to kidney transplantation: Added value of coronary calcium and epicardial adipose tissue

BackgroundPatient selection and optimal approach to risk stratification prior to kidney transplantation remain uncertain. We sought new predictors of an abnormal myocardial perfusion (MYP) stress test result. MethodsRetrospective study of 411 consecutive chronic kidney disease stages 4-5D patients awaiting kidney transplantation referred for risk stratification. PET-CT or SPECT-CT was used to assess MYP and quantify coronary artery calcium (CAC) and epicardial adipose tissue (EAT). Abnormal MYP was defined as a perfusion defect involving ≥5% of the left ventricular myocardium. ResultsFixed or reversible MYP defects were present in 41 patients (10%). Male sex, smoking, and history of cardiovascular disease were more prevalent; age was higher and CAC and EAT were greater in patients with MYP defects than in those with normal MYP. On multivariate logistic regression, EAT and CAC were independent predictors of abnormal MYP while diabetes mellitus showed a borderline association (P =.08). EAT added incremental diagnostic value to a model including age, CAC and diabetes mellitus [AUC 0.73 (95% CI 0.64-0.81) to 0.76 (95% CI 0.68-0.84; P =.02)]. Furthermore, the model containing EAT showed improved diagnostic discrimination. ConclusionsAbnormal MYP on screening stress testing appears to be rare in patients awaiting kidney transplantation suggesting an excess of testing. EAT and CAC may help predict what patients are at higher risk of developing abnormalities of MYP under stress.

Prothrombotic burden in a patient with recurrent thrombotic events: might an early assessment of thrombophilia be useful in the presence of a strong family history for vascular events?

A 55-year-old man (A. Z.) was admitted to Our Cardiac Step Down Unit of the tertiary center: Careggi Hospital, for an evaluation in the presence of a history of recurrent cardiovascular events. Classical cardiovascular risk factors: Hypertension on therapy with a good control, type 2 diabetes mellitus on metformin (3 g/day) with good glycemic control (glycated hemoglobin 5.6 %), high LDL cholesterol levels on statin treatment (rosuvastatin 20 mg/day) reaching a target of LDL 42 mg/dl; low HDL levels (24 mg/dl) on treatment, overweight (BMI 27.6). With regard to family history, almost all his relatives had suffered from a cardiovascular event (Fig. 1) at a young age. The first thrombotic event occurred at the age of 44 when he had an ischemic stroke without neurological sequelae treated with medical therapy. Aspirin therapy was spontaneously discontinued by the patient after about 4 years. At the age of 52, he had a STEMI treated with thrombolysis and subsequently underwent coronary angiography that demonstrated the presence of a critical stenosis in the right coronary artery (RCA) treated by angioplasty and drug-eluting stent (DES) implantation. One year later (on aspirin and clopidogrel), he suffered from an anterior STEMI initially treated with thrombolysis. A subsequent coronary angiography showed a critical stenosis of the left anterior descending artery (LAD), treated with balloon angioplasty and implantation of a DES on LAD and first and second diagonal branches. The course was complicated by acute intrastent thrombosis of the second diagonal branch, treated with the deployment of another DES. A few months later, a myocardial scintigraphy demonstrated signs of previous subendocardial necrosis in the mid-distal portion of the anterior wall and in the apex with mild inducible ischemia in the same area. At the age of 55—on dual antiplatelets—he had a recurrent inferior STEMI treated with thrombolysis, heparin and clopidogrel. After 1 day, a coronary angiography demonstrated a stenosis of LAD and circumflex artery and critical stenosis of RCA with image of complex plaque, which was treated with DES implantation. Previously implanted stents on first and second diagonal branches were patent. Echocardiography showed normal left chambers diameters and ventricular ejection fraction (EF 55 %) without valve diseases. The patient was then referred to our Cardiac Step Down Unit of Careggi Hospital. Because of his personal and family history, a thrombophilic screening was performed with these results: heterozygous mutations of both factor V Leiden and factor II G20210A; low levels of free protein S (52 %; n.v. \75 %); high levels of factor VIII (210 %; n.v. 60–150 %); elevated Lipoprotein(a) (893 mg/l; n.v.\300 mg/l) (Fig. 1). One month later, he was submitted to a myocardial perfusion stress test with dipyridamole, which was negative. A myocardial perfusion scintigraphy, a few months later, was positive for reversible uptake defects in LAD territory. Because of the presence of two stenoses on the LAD and the high estimated thrombotic risk, the patient was advised to undergo coronary artery bypass graft (CABG) but, after his refusal, a percutaneous coronary intervention (PCI) (triple DES implantation of the double stenosis on LAD II and on the critical stenosis of LAD III) was performed and E. Cecchi C. Giglioli Department of Heart and Vessels, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy

Evaluation of Molecular Breast Imaging in Women Undergoing Myocardial Perfusion Imaging with Tc-99m Sestamibi

Our objective was to explore the potential benefits of molecular breast imaging (MBI) as a screening technique in women undergoing stress myocardial perfusion studies. MBI was offered to women receiving Tc-99m sestamibi injection for myocardial perfusion stress testing. During the required waiting period after stress isotope injection, MBI was performed using a dedicated breast imaging gamma camera system. MBI examinations were interpreted by breast radiologists, with review of a recent mammogram in cases with positive MBI. Of 322 women enrolled, 313 completed MBI, comprising 5 with known breast cancer, 2 with known high-risk benign breast lesions, and 306 who were asymptomatic for breast disease with a recent negative mammogram. Analysis was limited to the 306 patients with no known breast disease. MBI was positive in 22 of 306, giving a recall rate of 7.2% (95% confidence interval [CI] 4.8-10.6]. MBI detected 4 new cancers, resulting in a supplemental diagnostic yield of 13.1/1000 women screened (95% CI 5.1-33.2). The number of cancers diagnosed per abnormal MBI examinations (PPV(1)) was 18% (4 of 22) (95% CI 7.3-38.5), and the number diagnosed per MBI-prompted biopsies (PPV(3)) was 44% (4 of 9) (95% CI 18.9-73.3). The addition of MBI to clinically indicated stress myocardial perfusion imaging studies in women results in a high diagnostic yield of newly detected breast cancers while generating a low rate of additional unnecessary workup.

Stent-Assisted Coil Embolization of a Large Fusiform Aneurysm of Proximal Anterior Descending Artery

A 37-year-old Asian American man presented with severe stable angina of recent onset over a period of 3 weeks. He was an active policeman, whose only significant past medical history was a prolonged febrile illness with a rash at age 5. Exercise myocardial perfusion stress test was strongly positive with ST depression in inferolateral leads and large reversible perfusion defects in the inferior, inferolateral, and lateral walls of the left ventricle. Cardiac catheterization revealed a large fusiform aneurysm of the proximal left anterior descending (LAD) artery, ectasia of the proximal circumflex artery with 95% narrowing, and an occluded right coronary artery with an occluded proximal aneurysm. (Figure 1). Figure 1. Coronary angiogram showing a proximal aneurysm of the left anterior descending (LAD) artery and ecstatic circumflex artery with severe stenosis inside the ecstatic segment. Coronary CT angiogram showed 3-dimensional extent of the aneurysms, stenoses, and, in particular, the LAD aneurysm's relation to the main pulmonary artery. The LAD aneurysm measured 11.7×17.7×24.2 mm, with a 2.5-mm diagonal artery arising from the side wall. (Figure 2). Figure 2. A, Computed tomography (CT) angiogram showing aneurysms and stenoses. B, CT angiogram showing …

Cardiac CT angiography compared with myocardial perfusion stress testing on downstream resource utilization

Nuclear myocardial perfusion stress (MPS) testing and cardiac computed tomographic angiography (CCTA) are commonly used noninvasive tests. Limited studies exist comparing their clinical and cost outcomes. We compared the clinical and cost outcomes of MPS with CCTA in a symptomatic cohort. We retrospectively identified 241 symptomatic patients without known coronary artery disease (CAD) who underwent MPS between May 2006 and April 2008. A comparison group of 252 age- and sex-matched symptomatic patients without known CAD underwent 64-slice CCTA during the same period. The primary outcome was the per-patient rate of posttest clinical evaluations and cardiac testing for the presenting symptom. Total direct costs were also compared. The group consisted of 44% women of mean age 53 ± 10 years. There were no differences in risk factors or pretest probability of obstructive CAD (83% intermediate risk) between groups. During mean follow-up of 30 ± 7 months, we found no difference between CCTA and MPS in per-patient rates of any posttest evaluation or testing, 24.6% versus 27.7% (P = 0.44), respectively. CCTA patients had lower utilization of invasive angiography (3.3% vs 8.1%; P = 0.02) and a nonsignificant trend toward reduced downstream cardiac testing (11.5% vs 17.0%; P = 0.08). Including the evaluation of significant incidental findings (7.1% in CCTA), mean direct costs were significantly lower using CCTA ($808; 95% CI, $611-$1005) compared with MPS ($1315; 95% CI, $1105-$1525; P <0.001). Low-intermediate risk patients without known CAD who underwent CCTA, compared with MPS, had similar rates of posttest evaluations, fewer invasive catheterizations, and lower overall evaluation costs.

Incidence of Caffeine in Serum of Patients Undergoing Dipyridamole Myocardial Perfusion Stress Test by an Intensive Versus Routine Caffeine History Screening

The coronary vasodilatory effect of dipyridamole is competitively blocked by caffeine. The purposes of this study were to (1) assess the incidence of having detectable serum caffeine and (2) evaluate whether an intensive caffeine history screening strategy was superior to routine history screening before dipyridamole myocardial perfusion imaging. One hundred ninety-four patients who were randomized to an intensive or a routine screening history strategy were prospectively evaluated. Serum caffeine levels were determined in all patients. Outcomes data, including death, nonfatal myocardial infarction, and history of revascularization, were obtained at 24 months. Nearly 1 in 5 patients (19%) who screened negative by history had detectable serum caffeine. In patients who screened negative by history, there was no statistically significant difference in the percentage of caffeine seropositivity between the intensive and routine arms (16% vs 22%, respectively, p = 0.31). The incidence of combined end points of death, myocardial infarction, or revascularization was 22.9% and 7.3% in patients with and without detectable serum caffeine, respectively (p = 0.01). In conclusion, despite initial negative results on screening by history, a considerably high percentage of patients had positive serum caffeine levels. These results do not support the use of an intensive screening strategy. Detectable serum caffeine was associated with a higher incidence of adverse outcomes.

Usefulness of 64-Slice Coronary Computed Tomographic Angiography in the Planning of Percutaneous Coronary Intervention

) with a 2-year history of adult-onset diabetes mellitus pre-sented with dyspnea on exertion and occasional chest discomfort. An electrocardiogram suggested previous inferior wall myocardial infarction of undetermined age. A myocardial perfusion stress test, performed at an outside institution, demonstrated inferior wall myocardial ischemia. The patient was initially unwill-ing to undergo invasive coronary angiography but was amenable to noninvasive, coronary computed tomo-graphic angiography (CCTA). A 64-slice gated CCTA demonstrated only mild narrowing of the left system

Percutaneous Coronary Intervention (PCI) in Combined FV and FVIII Deficiency with a Novel LMAN1 Mutation.

Abstract 4448 INTRODUCTIONPatients with congenital coagulation factor deficiencies undergoing PCI are at increased risk of both perioperative bleeding and thrombosis of coronary stents. Several cases of successful PCI have been described in patients with factor VIII (FVIII) and factor IX deficiency. We report on the first PCI in combined factor V (FV) and FVIII deficiency (F5F8D). F5F8D is an autosomal recessive disorder associated with moderate bleeding diathesis. This genetically heterogeneous disorder involves the genes LMAN1 and MCDF2, which encode for a cargo receptor complex that plays a key role in the trafficking of FV and FVIII from the endoplasmic reticulum to the golgi complex. CASE DISCUSSIONA 68 year old white male presented with dyspnea on exertion and palpitations. A myocardial perfusion stress test showed anteroseptal ischemia with a LVEF of 64%. He was referred for cardiac catheterization. He had life-long history of episodes of self-limiting mucosal bleeds, easy bruising and a large hematoma on his upper extremity provoked by a minor injury. Coagulation work up revealed a FV level of 11% and FVIII level of 7%. Before cardiac catheterization, the patient was given a loading dose of 30ml/kg of FFP. The trough levels of FV and FVIII were 37% and 31% after the procedure. The patient was given 25U/kg of recombinant FVIII (helixate FS ©) at 12 and 24 hours post PCI with a resultant FVIII level of 71% at 36 hours post PCI. Coronary angiography revealed the patient had a 95% stenosis of the left anterior descending artery. A metal stent was used to minimize the duration of antiplatelet therapy needed postoperatively. During the procedure anticoagulation was achieved using intravenous unfractionated heparin. There were no signs of local bleeding at the femoral access site through the postoperative period after using an Angioseal closure device. The patient was treated with clodipogrel 75 mg and aspirin 81 mg by mouth daily for 30 days after the procedure followed by aspirin alone long term. He had two episodes of mild self-limiting nose bleeds while on double antiplatelet therapy, no other bleeding. He remains well with no symptoms of cardiac ischemia at nine months after the procedure. Subsequent genetic analysis of both LMAN1 and MCFD2 genes showed two mutations: a novel 912delA mutation and a previously described 912-913insA mutation, both at the same location in exon 8. The mutations were confirmed first by sequencing, followed by cloning the PCR product and sequencing individual clones. Normally the LMAN1 gene has a string of 9A's at this location from 904 to 912, while our patient had 10 A's on one chromosome and 8 A's on the other chromosome. This could be explained by the patient having inherited one mutation on one chromosome and gaining a de novo mutation on the other chromosome, since this microsatellite repeat is a mutation hot spot. Unfortunately this question cannot be answered since no parent DNA was available. Informed consent was obtained prior to publication of this manuscript. CONCLUSIONSThis patient's presentation was consistent with published findings in other patients with F5F8 deficiency caused by LMAN1 mutations, with reported levels of FV 13.7% (range 1.7% to 35%) and FVIII 16% (range 2.2% to 35%). Our experience suggests that patients with F5F8D and mild bleeding diathesis can tolerate PCI for coronary artery disease followed by double antiplatelet therapy of limited duration and low-dose aspirin long term. Disclosures:No relevant conflicts of interest to declare.

An irregular wide-complex rhythm: What is the mechanism?

A 59-year-old man with a history of coronary artery disease and recent bypass surgery presented to the clinic for a routine post-hospitalization visit. He had suffered a myocardial infarction 17 years earlier. Progressive exertional angina prompted a myocardial perfusion stress test, which confirmed a large, severe inferolateral and septal wall infarct with mild border zone ischemia. Severe inferior wall hypokinesis with left ventricular ejection fraction of 40% was noted. Cardiac catheterization revealed three-vessel disease with extensive, diffuse calcifications.

Use of multidetector computed tomography after mildly abnormal myocardial perfusion stress testing in a large single-specialty cardiology practice

Data are limited on using 64-slice multidetector computed tomography (MDCT) as a gatekeeper to cardiac catheterization in patients with mild abnormalities on myocardial perfusion stress imaging (MPI). We compared the rate of invasive coronary angiography (ICA) within 6 months after finding mildly abnormal MPI results before and after implementing 64-slice MDCT. This retrospective cohort study included patients referred for follow-up based on a mildly abnormal MPI. Pre- and post-MDCT cohorts were matched according to age, sex, prior history of coronary artery disease (CAD), and presence of clinical symptoms (chest pain or exertional dyspnea or both). Case matching resulted in 154 patients in each cohort. The primary endpoint was the rate of ICA. From the clinical evaluation or MDCT results, 87 patients were referred for ICA, 60 (39%) in the pre-MDCT cohort and 27 (18%) in the post-MDCT cohort. Among those referred for ICA, 22 (14%) in the pre-MDCT cohort and 17 (11%) in the post-MDCT cohort underwent revascularization. Given the similar rate of revascularizations in both cohorts, we estimate that patients in the post-MDCT cohort were 86% less likely to receive ICA compared with patients in the pre-MDCT cohort (odds ratio = 0.14; 95% confidence interval, 0.06-0.33). During 6 months of follow-up, no clinical events were observed in either cohort for patients not referred to ICA. For patients with mildly abnormal MPI followed by clinical evaluation, MDCT examination was associated with a significant reduction in rate of referral to ICA.

Intermittent ST-Segment Depressions During Adenosine Stress Test

ST-segment depression during adenosine stress testing is usually a 1-time event during or after the test and is often related to ischemia due to severe 3-vessel disease. In this case report we describe a patient with severe 3-vessel disease who had intermittent ST-segment depression on the electrocardiogram during a myocardial perfusion stress test with adenosine. These intermittent ST depressions could be explained by possible adenosine-induced coronary spasm.