Israel Medical Association Journal

Objectives: To evaluate the predictive value of V/Q scanning in patients with impaired renal function.

Methods: We assessed all patients with impaired renal function who underwent V/Q scanning. The patients studied included those who also had CTPA (group 1) and those who did not (group 2). We recorded the results of V/Q scanning, chest X-rays, CTPA, D-dimer levels, ultrasound of deep veins, and clinical probability for PE (Wells' score) in group 1. CTPA results were considered true results. Anticoagulant treatment was documented in all the patients.

Results: Of the 45 patients in group 1, 12 (22%) had positive CTPA for PE. The positive predictive value (PPV) for patients with high probability results on V/Q scanning for PE was 30%. Restricting results to D-dimer levels ≥ 1000 ng/ml added little to this value. Restricting results to Wells’ score ≥ 7 resulted in 72% PPV. The negative predictive values for low or moderate probability were ~79 % and ~67% respectively. Of the 95 patients in group 2, all those with high probability for PE were treated with anticoagulants.

Conclusions: Patients with impaired renal function and high probability for PE on V/Q scanning had very low PPV for PE. Due to the lack of CTPA studies, patients with high probability for PE on V/Q scanning were treated with anticoagulants.

Objectives: To evaluate in a randomized control trial whether uninterrupted administration of angiotensin II (AngII) blockade medications influence estimated glomerular filtration rate (eGFR) in patients undergoing non-emergent coronary angiography.

Methods: Patients receiving treatment with angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACE-I/ARB) were recruited consecutively. The enrolled subjects were randomized into three groups at a 1:1:1 ratio: group A (ACE/ARB stopped 24 hours prior to the procedure and restarted immediately after the procedure), group B (ACE/ARB stopped 24 hours prior to the procedure and restarted 24 hours after the procedure), and group C (ACE/ARB continued throughout the study period). Plasma creatinine was measured and eGFR was calculated according to the Cockroft-Gault equation before and 48 hours after the coronary angiography. The primary endpoint was a change in eGFR at 48 hours.

Results: Groups A, B and C comprised 30, 31 and 33 patients respectively. The mean age of the study population was 65 ± 12 years and 67% were males. Fifty percent of the subjects had diabetes mellitus. The primary endpoint analysis showed that at 48 hours after the procedure there was no difference in ΔeGFR between groups A and C (4.25 ± 12.19 vs. 4.65 ± 11.76, P = 0.90) and groups B and C (3.72 ± 17.42 vs. 4.65 ± 11.76, P = 0.82). In post-hoc analysis the patients were clustered according to the following groups: medical alternation (group A and B) versus control (group C) and to baseline eGFR ≥ 60 ml/min vs. eGFR < 60 ml/min. In patients with baseline eGFR < 60 ml/min the ΔeGFR (baseline eGFR-eGFR 48 hours post-angiography) was significantly different between the intervention vs. control group (median 5.61 vs. median -2.19, P = 0.03 respectively). While in patients with baseline eGFR ≥ 60 ml/min there was no significant difference in ΔeGFR between the intervention and control groups.

Conclusions: ACE-I and ARB can safely be used before and after coronary angiography in patients with eGFR ≥ 60 ml/min. 

Background: Coronary computed tomography angiography (CCTA) is an established modality for ruling out coronary artery disease. However, it has been suggested that CCTA may be a source of non-negligible radiation exposure.

Objectives: To evaluate the potential degradation in coronary image quality when using prospective gated (PG) CCTA as compared with retrospective gated (RG) CCTA in chest pain evaluation.

Methods: The study cohort comprised 216 patients: 108 consecutive patients in the PG CCTA arm and 108 patients matched for age, gender and heart rate in the RG CCTA arm. Scans were performed using a 64-slice multidetector CT scanner. All 15 coronary segments were evaluated subjectively for image quality using a 5-point visual scale. Dose-length product was recorded for each patient and the effective radiation dose was calculated

Results: The PG CCTA technique demonstrated a significantly higher incidence of step artifacts in the middle and distal right coronary artery, the distal left anterior descending artery, the second diagonal, the distal left circumflex artery, and the second marginal branches. Nevertheless, the diagnostic performance of these scans was not adversely affected. The mean effective radiation doses were 3.8 ± 0.9 mSv vs.17.2 ± 3 mSv for PG CCTA and RG CCTA, respectively (P < 0.0001).

Conclusions: Artifacts caused by the PG CCTA technique (64 MDCT) scanners tended to appear in specific coronary segments but did not impair the overall diagnostic quality of CCTA and there was a marked reduction in radiation exposure. We conclude that 64-slice PG CCTA is suitable for clinical use, especially for acute chest pain "fast track" evaluation targeted at relatively young subjects in a chest pain unit.
 

Background: Coronary CT angiography is an accurate imaging modality; however, its main drawback is the radiation dose. A new technology, the "step and shoot," which reduces the radiation up to one-eighth, is now available.

Objectives: To assess our initial experience using the "step-and-shoot" technology for various vascular pathologies.

Methods: During a 10 month period 125 consecutive asymptomatic patients (111 men and 14 women aged 25–82, average age 54.9 years) with various clinical indications that were appropriate for step-and-shoot CCTA[1] (regular heart rate < 65 beats/minute and body weight < 115 kg) were scanned with a 64-slice multidetector computed tomography Brilliance scanner (Philips, USA). The preparation protocol for the scan was the same as for the regular coronary CTA. All examinations were interpreted by at least one experienced radiologist and one experienced interventional cardiologist. The quality of the examinations was graded from 1 (excellent imaging quality of all coronary segments) to 4 (poor quality, not diagnostic). There were 99 patients without a history of coronary intervention, 13 after coronary stent deployment (19 stents), and 3 after coronary artery bypass graft.

Results: Coronary interpretation was obtained in 122 examinations (97.6%). The imaging quality obtained was as follows: 103 patients scored 1 (82.4%), 15 scored 2 (12%), 4 scored 3 (3.2%) and 3 scored 4 (2.4%). The grades were unrelated to cardiac history or type of previous examinations. Poor image quality occurred because of sudden heart rate acceleration during the scan (one patient), movement and respiration (one patient), and arrhythmia and bad scan timing (in one). Two patients were referred to percutaneous coronary intervention based on the CCTA findings, which correlated perfectly.

Conclusions: Step-and-shoot CCTA is a reliable technique and CCTA algorithm comparable to the regular CCTA. This technique requires the lowest radiation dose, as compared to other coronary imaging modalities, that can be used for all CCTA indications based on the inclusion criteria of low (> 65 bpm) and stable heart rate.

Background: On-site cardiac surgery is not widely available in developing countries despite a high prevalence of coronary artery disease.

Objectives: To analyze the safety, feasibility and cost-effectiveness of transradial percutaneous coronary intervention without on-site cardiac surgery in a community hospital in a developing country.

Methods: Of the 174 patients who underwent PCI[1] for the first time in our center, we analyzed two groups: stable coronary disease and acute myocardial infarction. The primary endpoint was the rate of complications during the first 24 hours after PCI. We also analyzed the length of hospital stay and the rate of hospital readmission in the first week after PCI, and compared costs between the radial and femoral approaches.

Results: The study group comprised 131 patients with stable coronary disease and 43 with acute MI[2]. Among the patients with stable coronary disease 8 (6.1%) had pulse loss, 12 (9.16%) had on-site hematoma, and 3 (2.29%) had bleeding at the site of the puncture. Among the patients with acute MI, 3 (6.98) had pulse loss and 5 (11.63%) had bleeding at the site of the puncture. There were no cases of atriovenous fistula or nerve damage. In the stable coronary disease group, 130 patients (99%) were discharged on the same day (2.4 ± 2 hours). In the acute MI group, the length of stay was 6.6 ± 2.5 days with at least 24 hours in the intensive care unit. There were no hospital readmissions in the first week after the procedure. The total cost, which includes equipment related to the specific approach and recovery room stay, was significantly lower with the radial approach compared to the femoral approach (US$ 500 saving per intervention).

Conclusions: The transradial approach was safe and feasible in a community hospital in a developing country without on-site cardiac surgery backup. The radial artery approach is clearly more cost effective than the femoral approach.

Background: Renal artery stenosis is one of the most frequent causes of secondary hypertension. Appropriate methods for screening, diagnosis and therapy are currently under debate.

Objectives: To evaluate and recommend methods for screening and diagnosing renal artery stenosis, and to assess the clinical outcomes of renal artery stenting.

Methods: A total of 450 patients undergoing non-emergent coronary angiography fulfilled the selection criteria for selective renal arteriography; those with severe (luminal narrowing ≥ 70%) renal artery stenosis underwent percutaneous transluminal renal angioplasty with renal artery stenting.

Results: Of 166 patients (36.9%) with renal artery stenosis, 41 (9.1%) had severe stenosis that required renal artery stenting, and 83% had ostial renal stenosis. The primary success rate was 100% and there were no complications. During the follow-up period, two patients required a second PTRA[1]. After stent deployment, significant reductions were observed in systolic and diastolic pressures (P < 0.001 and P = 0.01, respectively) and in the number of antihypertensive drugs used by the patients (P < 0.001). These reductions were sustained during follow-up. Hypertension was cured (systolic blood pressure < 130 mmHg) in 9 (21.4%) and improved in 27 (64.3%) patients. Plasma creatinine did not change significantly.

Conclusions: Selective renal angiography is an effective diagnostic tool for identifying symptomatic cases of renal artery stenosis in patients undergoing coronary angiography. Our finding of a high success rate and low complication rate supports the use of primary renal artery stenting in symptomatic patients with renal artery stenosis.

Background: Cardiac computed tomography scans influde several extra-cardiac structures such as mediastinum, lung parenchyma and upper abdominal organs. A variety of abnormalities in those structures might be clinically important and in some cases might explain the patient's complaints.

Objectives: To analyze consecutive cardiac computed tomography examinations for the prevalence and clinical significance of extra-cardiac findings.

Methods: Cardiac CT scans of 134 sequential patients (104 males, 30 females) aged 20–77 years (mean 54 years) with suspected coronary artery disease were prospectively and independently reviewed by a consensus of two radiologists for the presence of lung, mediastinal, pleural, upper abdominal and skeletal abnormalities. CT scans with extra-cardiac abnormalities were divided into two groups: group A – defined as "clinically significant" or "potentially significant findings" – consisted of patients requiring further evaluation or follow-up, and group B – "clinically non-significant findings."

Results: Extra-cardiac abnormalities were found in 103 of the 134 patients (76.8%). Group A abnormalities were found in 52/134 patients (39%), while group B abnormalities were seen in 85/134 (63%). The most common abnormalities in group A were non-calcified lung nodules (> 4 mm) noted in 17/134 patients (13%), followed by enlarged mediastinal lymph nodes (> 10 mm) in 14/134 (10%), diaphragmatic hernia (2 cm) in 12/134 (9%), moderate or severe degenerative spine disease in 12/134 (9%), and emphysema and aortic aneurysm in 6 patients each (4.5%). A malignant lung tumor was noted in one patient.

Conclusions: There is a high prevalence of non-cardiac abnormalities in patients undergoing CCT[1]. Clinically significant or potentially significant findings can be expected in 40% of patients who undergo CCT, and these will require further evaluation and follow-up. The reporting radiologist should be experienced in chest imaging and aware of the large variety of non-cardiac findings in CCT that might explain the patient's complaints. 

Background: Cardiac computed tomography angiography is a relatively new imaging modality to detect coronary atherosclerosis.

Objectives: To explore the diagnostic value of CTA[1] in assessing coronary artery disease among asymptomatic patients.

Methods: In this retrospective single-centered analysis, 622 consecutive patients underwent CTA of coronary arteries between November 2004 and May 2006 at the Mor Institute for Cardiovascular Imaging in Bnei Brak, Israel. All patients were asymptomatic but had at least one risk factor for atherosclerotic CAD[2]. The initial 244 patients were examined with the 16-slice Brilliance CT scanner (Philips, Cleveland, OH, USA), and in the remaining 378 patients the 64-slice scanner (GE Healthcare, The Netherlands) with dedicated cardiac reconstruction software and electrocardiography triggering was used. Scanning was performed in the cranio-caudal direction. Images reconstructed in different phases of the cardiac cycle using a retrospective ECG-gated reconstruction algorithm were transferred to a dedicated workstation for review by experienced CT radiologists and cardiologists.

Results: Of 622 patients, 52 (8.4%) had severe obstructive atherosclerosis (suspected ≥ 75% stenosis) according to CTA interpretation. Invasive coronary angiography was performed in 48 patients while 4 patients had no further procedure. A non-significant CAD (e.g., diameter stenosis < 70%) was identified in 6 of 48 patients (12%) by selective coronary angiography. Forty-two patients showed severe CAD with at least one lesion of ≥ 70% stenosis. Percutaneous coronary intervention was performed in 35 patients and coronary artery bypass grafting surgery in the other 4 patients. Angioplasty procedures were successful in all 35 patients and stents were utilized in all cases without complications. No further complications occurred among the study cohort undergoing either PCI[3] or surgery. The 6 month survival rate in these patients was 100%.

Conclusions: Non-invasive coronary CTA appears to be a reliable technique, with reasonably high accuracy, to detect obstructive atherosclerosis in asymptomatic high risk patients for atherosclerotic CAD.