Are intraventricular gradients a cause of false positive treadmill exercise tests?

BACKGROUND: Treadmill exercise testing has low specificity for the detection of significant epicardial coronary artery disease (CAD). A possible mechanism to explain some of the false positives is transient subendocardial ischemia induced by intraventricular gradients (IVG) during stress. The development of IVG during dobutamine stress echocardiography (DSE) occurs in 8-38% of non-selected populations. OBJECTIVES: To determine: 1. the prevalence of IVG in a selected population of false positives on treadmill stress testing; 2. whether this prevalence is different from that described for non-selected populations; 3. whether patient characteristics are related to the presence of IVG; 4. the relation between the presence of IVG and the occurrence of ECG abnormalities, symptoms and blood pressure. METHODS AND RESULTS: We evaluated 50 consecutive patients with false positive treadmill stress tests (normal CT coronary angiography, nuclear perfusion tests or angiography) with DSE (2D and Doppler evaluation). All DSE exams were negative for ischemia. Stress-induced IVG was seen in 34 of the 50 patients (68%) and 16 patients (32%) did not develop IVG (p<0.05). The prevalence of IVG in our selected population (68%) was significantly higher than that described for non-selected populations (8-38%) (p<0.001). Most patient characteristics (gender, age, risk factors for CAD, treatment with beta-blockers/calcium antagonists, significant valvular disease/left ventricular hypertrophy [LVH], symptoms, and blood pressure during stress) were not statistically associated with the prevalence of IVG (p>0.05). However, the presence of IVG was associated with the occurrence of ischemic ST depression during dobutamine stress echo (p<0.05). CONCLUSIONS: 1. The prevalence of IVG during dobutamine stress echocardiography in a selected population of false positives on treadmill stress testing is very high, occurring in more than two-thirds of patients. 2. This prevalence is significantly higher than that described for non-selected populations. 3. Age, gender, risk factors for CAD, treatment with beta-blockers/calcium channel antagonists, significant valvular disesase/LVH, symptoms and blood pressure during stress were not associated with the presence or absence of IVG. 4. The presence of IVG is associated with the occurrence of ischemic ST changes during dobutamine stress echocardiography.

Usefulness of a new miniaturized echocardiographic system in outpatient cardiology consultations as an extension of physical examination.

BACKGROUND: The aim of this study was to assess the usefulness of a new miniaturized echocardiographic system (MS) to perform bedside echocardiography in initial outpatient cardiology consultations, in addition to physical examination. METHODS: One hundred eighty-nine patients referred for initial cardiology outpatient consultations at two tertiary hospitals in two countries were studied. Each patient was submitted to physical examination followed by MS assessment. Scanning time, the number of examinations with abnormal results after physical examination and the MS, and the information obtained by physical examination alone and followed by the MS (in terms of its importance in reaching a diagnosis, in the necessity of performing routine echocardiography, and in the decision to release the patient from the outpatient clinic) were assessed. RESULTS: The scanning time with the MS was 180 ± 86 seconds. Its use after physical examination led to diagnoses in 141 patients (74.6%) and to an additional 37 patients (19.6%) being released from the outpatient clinic. After physical examination followed by MS assessment, only 64 patients (33.9%) were sent to the echocardiography lab. The MS modified the decision of whether to send a patient to the echocardiography lab, with referral determined by the MS in 27 patients (14.3%) and no referral determined by the MS in 58 patients (30.7%). CONCLUSIONS: The new MS caused a negligible increase in the duration of consultations. It showed additive clinical value over physical examination, increasing the number of diagnoses, reducing the use of unnecessary routine echocardiography, increasing the number of adequate echocardiographic studies, and determining a large number of releases from the outpatient clinic.

Playing games with a thrombus: a dangerous match. Paradoxical embolism from a huge central venous cathether thrombus: a case report.

Thromboembolism is a major cause of death in cancer patients. The association between paraneoplastic hypercoagulability of oncological patients and long-term central venous catheters (CVC) may result in CVC associated thrombosis. Patent Foramen Ovale (PFO), especially when associated with atrial septal aneurysm (ASA) is a risk factor for paradoxical embolism. We report a case of paradoxical embolism with stroke in an oncological patient with a huge CVC thrombus playing "ping-pong" with an hypermobile ASA with a PFO. We review the management of hypercoagulability in oncologic patients and discuss the potential role of routine transthoracic echocardiography before the implantation of long term central venous catheters to identify predisposing conditions to paradoxical embolism and select patients for anticoagulant therapy.

Are intraventricular gradients with dobutamine a cause of false positive treadmill stress tests?

An asymptomatic 40-year-old man with no conventional risk factors for coronary artery disease had a positive treadmill stress test based on ECG criteria. Coronary CT angiography showed a small plaque in the left anterior descending artery and dobutamine-atropine stress echocardiography was negative for myocardial ischemia but showed a significant outflow gradient (100 mmHg) during pharmacological stress.

Percutaneous aortic valvuloplasty in inoperable symptomatic severe aortic stenosis in the very elderly.

Aortic valve replacement is the first therapeutic option in patients with symptomatic severe aortic stenosis. Given the fact that percutaneous aortic valve implantation is a relatively new procedure and the need for palliative treatment in symptomatic patients with a high surgical risk, percutaneous balloon aortic valvuloplasty is still employed. The authors describe two cases of percutaneous balloon aortic valvuloplasty in very elderly patients with severe calcified aortic stenosis not suitable for cardiac surgery, exacerbated in one case by significant coronary artery disease and left ventricular systolic dysfunction. The authors also review the role of this procedure in current interventional cardiology.

Anomalous origin of the circumflex coronary artery--two case reports.

As shown in many series, congenital coronary artery anomalies are found in 0.6 to 1.5% of patients undergoing coronary angiography. Various types of coronary anomalies have been described, many involving the circumflex artery. The second most common anomaly is of the circumflex arising from the right sinus of Valsalva, while origin in the right coronary artery is also frequent. The most common anomaly is absence of the left main coronary artery, the anterior descending and circumflex arteries originating separately in the left coronary sinus. Such anomalies are usually benign, although earlier and more aggressive atherosclerosis is more likely than in normal coronaries and myocardial ischemia can result. Although rare, this can manifest as sudden death. Conventional coronary angiography may be unable to determine the three-dimensional course of the anomalous vessel. The development of multislice computed tomography and its application to cardiac imaging mean that it is now possible to visualize the coronary arteries non-invasively and to obtain more accurate information on their proximal course. We present two cases of congenital anomaly of the circumflex coronary artery diagnosed with the aid of multislice computed tomography.

Acute coronary syndromes in smokers: clinical and angiographic characteristics.

UNLABELLED: Smoking is a major and reversible risk factor for coronary artery disease. The present work aims to define the risk factors, angiographic and clinical characteristics and evolution of acute coronary syndromes in smokers. METHODS: We studied 521 consecutive patients with acute coronary syndrome admitted to the intensive care unit who underwent catheterization. We assessed the population in terms of risk factors, pathology (unstable angina or acute myocardial infarction), coronary morphology, left ventricular function, the need for intervention, evolution and complications over a one-year period. The characteristics of smokers were then compared with those of non-smokers. RESULTS: Of the 521 patients with acute coronary syndrome (391 men), 182 (35 %) were smokers. The smokers were younger than the non-smokers (56.3+/-9.5 versus 66.4 +/- 7.8; p < 0.001), were more frequently male (91 versus 66%; p < 0.001), and presented more risk factors (43% with 3 or more risk factors versus 17% in non-smokers; p < 0.001), more obesity (11 versus 5%; p < 0.01), and less diabetes (19 versus 37%; p < 0.001). Smokers presented greater prevalence of acute myocardial infarction (57 versus 40%; p < 0.001) and less unstable angina. Coronary morphology was not significantly different in smokers compared to non- smokers and left ventricular function after the aculte coronary syndrome was similar in both groups. Smokers less frequently underwent surgery during hospitalization (22% versus 35%; p < 0.01) but needed angioplasty as often as non-smokers (48% versus 16%; NS). Smokers presented more frequent complications (angina, heart failure, re-infarction or CABG) than non-smokers (26% versus 17%; p < 0.01), during the first year of follow-up. One-year mortality was similar in both groups. The results were not significantly different when adjusted for gender. CONCLUSIONS: On average, acute coronary syndrome occurred 10 years earlier in smokers than in non-smokers. The former generally presented more risk factors, lower prevalence of diabetes and higher of obesity, more myocardial infarctions and less unstable angina. After the acute coronary syndrome, at one year, smokers presented more complications than non-smokers but had similar mortality.