CCS/CAR/CANM/CNCS/CanSCMR joint position statement on advanced noninvasive cardiac imaging using positron emission tomography, magnetic resonance imaging and multidetector computed tomographic angiography in the diagnosis and evaluation of ischemic heart disease--executive summary.

BACKGROUND: Over the past few decades, advanced imaging modalities with excellent diagnostic capabilities have emerged. The aim of the present position statement was to systematically review existing literature to define Canadian recommendations for their clinical use. METHODS: A systematic literature review to 2005 was conducted for positron emission tomography (PET), multidetector computed tomographic angiography and magnetic resonance imaging (MRI) in ischemic heart disease. Papers that met the criteria were reviewed for accuracy, prognosis data and study quality. Recommendations were presented to primary and secondary panels of experts, and consensus was achieved. RESULTS: Indications for PET include detection of coronary artery disease (CAD) with perfusion imaging, and defining viability using fluorodeoxyglucose to determine left ventricular function recovery and/or prognosis after revascularization (class I). Detection of CAD in patients, vessel segments and grafts using computed tomographic angiography was considered class IIa at the time of the literature review. Dobutamine MRI is class I for CAD detection and, along with late gadolinium enhancement MRI, class I for viability detection to predict left ventricular function recovery. Imaging must be performed at institutions and interpreted by physicians with adequate experience and training. CONCLUSIONS: Cardiac imaging using advanced modalities (PET, multidetector computed tomographic angiography and MRI) is useful for CAD detection, viability definition and, in some cases, prognosis. These modalities complement the more widespread single photon emission computed tomography and echocardiography. Given the rapid evolution of technology, initial guidelines for clinical use will require regular updates. Evaluation of their integration in clinical practice should be ongoing; optimal use will require proper training. A joint effort among specialties is recommended to achieve these goals.

Clinical, physiologic, anatomic and procedural factors predictive of restenosis after percutaneous transluminal coronary angioplasty.

In a recent prospective double-blind placebo-controlled trial, a combination of aspirin and dipyridamole was not associated with a reduction in the rate of restenosis within the 1st 6 months after coronary angioplasty. The purpose of this study was to determine whether clinical, anatomic or procedural factors were predictive of the observed restenosis rates in that prospective trial. A total of 247 patients and 280 segments underwent follow-up angiography and quantitative coronary angiographic analysis between 4 and 7 months after coronary angioplasty. Two baseline clinical characteristics--angina class and duration of angina in months--were related to the rate of restenosis by univariate analysis. Patient-related stepwise logistic regression analysis identified severity of angina as the only clinical predictor of restenosis. Three univariate baseline anatomic characteristics--percent diameter stenosis before angioplasty, stenosis greater than 10 mm in length and calcific stenosis--and two early postangioplasty characteristics--residual percent diameter stenosis and residual mean pressure gradient--were predictive of restenosis. Of these, only two--length of stenosis and residual percent diameter stenosis--were independently related to restenosis by multivariate analysis and only the former is identifiable before the procedure. It is concluded that in prospective studies in contrast to retrospective studies, few clinical and anatomic factors appear to be predictive of restenosis after coronary angioplasty.

Comparison by quantitative angiographic assessment of coronary stenoses of one view showing the severest narrowing to two orthogonal views.

Quantitative coronary arteriographic measurements were compared in 2 orthogonal views with the view that clearly showed the stenosis at its most severe in 147 lesions from 147 patients before, immediately after and 6 months after PTCA. In 21 of 147 patients (14%), 2 views could not be measured for technical reasons, even though all angiographers had tried to film 2 views. Lesion severity was slightly worse for 1 compared with 2 views (3.3 +/- 3.3% before PTCA, 3.6 +/- 3.8% after PTCA and 3.1 +/- 3.8% at follow-up). Similarly, minimal diameter was less for 1 view (0.11 +/- 0.09 mm before PTCA, 0.15 +/- 0.12 mm after PTCA and 0.13 +/- 0.09 mm at 6 months). When this systematic difference was taken into account, the 2 methods were within +/- 0.1 mm for minimal diameter in 288 of 376 measurements (77%) and within +/- 0.2 mm in 96%. For percent diameter stenosis the 2 methods were within +/- 5% in 90% and within +/- 10% in all but 2.7% (10 of 376). Thus, for routine clinical assessment, measurement of 1 view is adequate; for research purposes orthogonal views may sometimes be required.

Clinical experience with the right gastroepiploic artery in coronary artery bypass grafting.

The excellent long-term results with the internal mammary artery for coronary artery bypass grafting have prompted the search for other conduits with similar characteristics. From December 1989 to December 1991, the right gastroepiploic artery (RGEA) has been used as an in situ graft to the posterior descending coronary artery in 51 patients at the Montreal Heart Institute. The patients' age averaged 50 +/- 11 years. Three-vessel coronary artery disease was present in 41 patients and two-vessel disease in the remaining 10 patients. In all but 1 patient, bilateral internal mammary artery grafting was performed in addition to RGEA grafting. The number of grafts per patient averaged 3.2 +/- 0.8. There was no operative mortality. Morbidity was minimal with only myocardial infarction and a pleural effusion in 1 patient. In 1 patient, a splenectomy had to be performed because of iatrogenic tear during dissection of the RGEA. The average hospital stay was 8.2 +/- 2.6 days. Enteral nutrition was resumed on average 2 days after operation. Angiographic evaluation of RGEA grafts was performed before discharge or within the first month after surgery in 31 patients. In 28 patients (28/31, 90%) the RGEA graft was patent, two grafts were occluded, and in the remaining patient, the graft could not be visualized due to technical difficulties during angiography. A second angiographic evaluation was performed in 5 patients, 1 year after operation. Four RGEAs were patent and 1 was occluded. Clinical follow-up averaged 4 months (range 1 to 15 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Transluminal angioplasty of the subclavian artery in patients with internal mammary grafts.

From January 1987 to January 1992, 11 patients underwent percutaneous transluminal angioplasty (PTA) for the treatment of subclavian artery stenosis before or after coronary artery bypass grafting (CABG) using the internal mammary artery (IMA). There were 8 men and 3 women, with a mean age of 57 +/- 7 years. Four patients had PTA 1 to 4 months before undergoing CABG with IMA grafts, because of either asymptomatic supraclavicular murmurs or neurologic symptoms. Seven patients underwent PTA 2 to 37 months after CABG with IMA grafts, because of recurrent angina. Subclavian artery stenosis was on the left side in 9 patients, the right side in 1 patient, and bilateral in 1 patient. Ten PTA procedures were successful in 9 patients. All patients with post-CABG angina had reversal of the ischemia. There were three complications: one femoral artery thrombosis, one brachial plexus hematoma after an axillary approach, and one acute pulmonary edema after the procedure. Follow-up after PTA ranged from 1 to 60 months (mean, 38 +/- 17 months). Nine patients had no angina at follow-up and 2 had stable angina (class II) upon exertion. Upper-limb Doppler studies showed no evidence of restenosis in any of these patients at a mean follow-up of 38 months. Subclavian artery PTA is a useful alternative to IMA bypass grafting in patients with subclavian artery stenosis discovered preoperatively, and it is the treatment of choice for those presenting with post-CABG angina due to subclavian artery stenosis proximal to an IMA graft.

Coronary endarterectomy revisited: mid-term angiographic results.

OBJECTIVES: To evaluate the value of concomitant coronary endarterectomy (CE) in the modern era of coronary revascularization. METHODS: Retrospective study. Twenty-eight patients (five women; 23 men) who underwent coronary endarterectomy were angiographically studied 24 +/- 22 months after the procedure. Necessity CE (vessel completely occluded or with lumen less than 1 mm) was performed on the left anterior descending (LAD) artery in 12 patients, the right coronary artery (RCA) in nine, the obtuse marginal artery (OM) in five and a diagonal branch in two patients. Conduits used for revascularization were the internal thoracic artery (ITA) in 11 (all anastomosed to the LAD; combined with saphenous vein patch in four) and a saphenous vein graft in 17 patients. Mean atherosclerotic core length was 3.3 +/- 1.8 cm. An average of 3.1 +/- 0.7 distal anastomoses per patient were constructed, with mean aortic cross-clamp and cardiopulmonary bypass times of 61.2 +/- 20.2 mins and 94.0 +/- 23.5 mins, respectively. RESULTS: Overall, angiographic patency rate was 71% (20 of 28) for the endarterectomized vessels (12 of 12 LAD, six of nine RCA, two of five OM and none of two diagonal arteries) and 93% (57 of 61) for the nonendarterectomized vessels. Among the eight patients with occluded CE vessels, two sustained a perioperative myocardial infarction, five developed angina during follow-up, and one patient remained asymptomatic. CONCLUSION: Necessity CE demonstrates acceptable mid-term patency. In addition, this study showed excellent patency following CE of the LAD revascularized with the ITA, with or without only a saphenous vein patch.

Pseudoaneurysm after Bentall repair: magnetic resonance imaging assessment.

The prevalence and natural history of pseudoaneurysms (PA) following Bentall procedure has not been established. To determine the follow-up of PA in patients, the authors report their experience with magnetic resonance imaging (MRI) since 1988. Spin-echo technique suspected PA in 19 of the 27 patients who underwent aortic valve and ascending aortic replacement between 1980 and 1991. Mean PA diameter was less than 4 cm in 13 patients (group 1) and at least 4 cm in six patients (group 2). Two patients in group 1 were lost at follow-up while two others in this group died after first spin-echo examination (one death was related to PA formation). Repeated MRIs were thus possible in nine patients in group 1 and in all patients in group 2, averaging 2.2 +/- 1.1 examinations per patient for group 1 and 1.8 +/- 1.1 for group 2. PA assessed in six group 1 patients and one group 2 patient suggested thrombosed PA or postoperative hematoma. PA remained stable in two group 1 patients and one group 2 patient. One patient from group 1, in whom PA increased at follow-up, died suddenly. Four patients in group 2 required correction of PA, which had increased in diameter. Recently, addition of cine MRI has allowed visualization of turbulent flow within PA, thus increasing MRI specificity for PA diagnosis. In conclusion, MRI constitutes a reliable noninvasive imaging technique for diagnosis and follow-up of PA after Bentall repair.

Post-traumatic thoracic pseudoaneurysm repair with an endoluminal expandable stent.

Recent technological improvement has allowed endoluminal correction of thoracic and abdominal aortic aneurysm through percutaneous insertion of expandable stents. A woman who presented with chronic pseudoaneurysm of the thoracic aorta 10 years after being in a car accident is presented. A Talent stent was introduced through the femoral artery and successfully deployed under fluoroscopic guidance across the aneurysmal defect. Recovery was uneventful, and 12 months later the patient remained asymptomatic.

Measurement of odor intensity by an electronic nose.

The possibility of using electronic noses (ENs) to measure odor intensity was investigated in this study. Two commercially available ENs, an Aromascan A32S with conducting polymer sensors and an Alpha M.O.S. Fox 3000 with metal oxide sensors, as well as an experimental EN made of Taguchi-type tin oxide sensors, were used in the experiments. Odor intensity measurement by sensory analysis and EN sensor response were obtained for samples of odorous compounds (n-butanol, CH3COCH3, and C2H5SH) and for binary mixtures of odorous compounds (n-butanol and CH3COCH3). Linear regression analysis and artificial neural networks (ANN) were used to establish a relationship between odor intensity and EN sensor responses. The results, suggest that large differences in sensor response to samples of equivalent odor intensity exist and that sensitivity to odorous compounds varies according to the type of sensors. A linear relationship between odor intensity and averaged sensor response was found to be appropriate for the EN based on conducting polymer sensors with a correlation coefficient (r) of 0.94 between calculated and measured odor intensity. However, the linear regression approach was shown to be inadequate for both ENs, which included metal oxide-type sensors. Very strong correlation (r = 0.99) between measured odor intensity and calculated odor intensity using the ANN developed were obtained for both commercial ENs. A weaker correlation (r = 0.84) was found for the experimental instrument, suggesting an insufficient number of sensors and/or not enough diversity in sensor responses. The results demonstrated the ability of ENs to measure odor intensity associated with simple mixtures of odorous compounds and suggest that ANN are appropriate to model the relationship between odor intensity measurement and EN sensor response.

[Multifocal percutaneous transluminal coronary and aortic angioplasty. Apropos of a case]. / L'angioplastie transluminale percutanée multifocale, coronaire et aortique. A propos d'un cas.

The authors report a case of percutaneous transluminal angioplasty performed successfully in 2 stages on the right coronary artery and the abdominal aorta in a woman with a post-infarction angina and intermittent claudication. The invasive and non-invasive control investigations at 6 and 18 months after coronary dilatation confirmed good clinical results and the stability of the excellent result of the immediate postoperative angiographic control. As for the aortic dilation, the persistent functional improvement nearly 2 years later was sufficient evidence of the success of the procedure.

[Results of percutaneous dilatation of subclavian artery stenosis in patients with internal mammary grafts]. / Résultats de la dilatation percutanée de sténoses de l'artère sous-clavière chez des malades porteurs de greffons mammaires internes.

From January 1987 to January 1992, 11 patients underwent percutaneous transluminal angioplasty (PTA) for subclavian artery (SCA) stenosis before or after coronary artery bypass grafting (CABG) with the internal mammary artery (IMA). There were 8 men and 3 women with a mean age of 57 +/- 7 years. Four patients had PTA 1 to 4 months before undergoing CABG with IMA grafts, because of asymptomatic subclavian murmurs or of neurologic symptoms. Seven patients underwent PTA 2 to 37 months after CABG with IMA grafts, because of recurrent angina. Subclavian artery stenosis was present on the left side in 9 patients, the right side in one patient, and was bilateral in one patient. Ten PTA procedures were successful in 9 patients. All patients with post-CABG angina had reversal of the ischemia. Three complications occurred: 1 femoral artery thrombosis, 1 branchial plexus hematoma after an axillary approach, and 1 acute pulmonary edema after the procedure. Follow-up ranged from 1 to 60 months after PTA (mean 38 +/- 17 months). Nine patients had no angina at follow-up and 2 presented with stable angina (class II) upon exertion. Upper-limb Doppler studies showed no evidence of restenosis in all of these patients, at a mean follow-up of 38 months. Subclavian artery percutaneous transluminal angioplasty is a useful alternative for candidates to IMA bypass grafting with SCA stenosis discovered pre-operatively, and it is the treatment of choice for those presenting with post-CABG angina due to SCA stenosis proximal to an IMA graft.

[Place of gastroepiploic and epigastric arteries in myocardial revascularization]. / Rôle des artères gastroépiploïques et épigastriques dans la chirurgie de revascularisation du myocarde.

Seventy patients underwent coronary artery bypass grafting with the right gastroepiploic artery or the inferior epigastric artery between 1989 and 1992 at the Montreal Heart Institute. There were 68 men and 2 women with a mean age of 53 +/- 8 years, the right gastroepiploic artery in situ was anastomosed to the right coronary artery in 55 patients and the inferior epigastric artery (free graft) was used in 18 patients. Double internal thoracic artery grafts were used in all patients. Early patency rate of right gastroepiploic artery and inferior epigastric artery grafts was 91% (31/34 grafts) and 57% (8/14 grafts) respectively. One patient died after surgery (1.4%) from acute renal failure and one patient developed an acute myocardial infarction (1.4%) at surgery. Fifty-five patients (55/57, 96%) showed no evidence of angina at the last follow-up. In conclusion, patency rate and clinical results of coronary artery bypass grafting with the right gastroepiploic artery graft were excellent and patency rate of inferior epigastric artery graft was unsatisfactory. We suggest that epigastric artery grafts should be used with caution, only when no other alternative is available.

[Magnetic resonance imaging in the diagnosis and follow-up of false aneurysms after Bentall's operation]. / La résonance magnétique pour le diagnostic et le suivi des pseudoanévrismes après intervention de type Bentall.

The prevalence and natural history of pseudo-aneurysm (PA) following Bentall procedure has not been established. To determine the follow-up of such patients, we report our experience with magnetic resonance imaging (MRI) used since 1988. At first, spin-echo exam, PA was suspected in 19 patients among 27 patients who underwent aortic valve and ascending aortic replacement between 1980 and 1991. Mean PA diameter was < 4 cm in 13 patients (group 1) and > or = 4 cm in six patients (group 2). Two patients of group 1 were lost at follow-up while two others died after the first spin-echo exam, one death being related to PA formation. Repeated MRIs were done in nine patients of group 1 and all patients of group 2 averaging respectively 2.2 +/- 1.1 exams per patient for group 1 and 1.8 +/- 1.1 for group 2. PA regressed in six patients of group 1 and one patient of group 2 thus suggesting thrombosed PA or postoperative haematoma. PA remained stable in two patients of group 1 and one patient of group 2. One patient of group 1 in whom PA increased at follow-up died suddenly. Four patients of group 2 required surgical correction of their PA. One of these patients died of massive hemoptysis 2 months following reintervention. Recently, addition of cine MRI allows visualization of turbulent flow within the PA thus increasing MRI specificity for PA diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

[Vascular radiology without hospitalization. Apropos of 306 angiographies and/or peripheral percutaneous transluminal angioplasties done on an ambulatory basis]. / La radiologie vasculaire sans hospitalisation. A propos de 306 angiographies et/ou angioplasties transluminales percutanées périphériques réalisées en ambulatoire.

A study on the safety of outpatient angiography and interventional radiology was undertaken. The authors reviewed the medical files of 286 patients and conducted a late telephone inquiry in 249 patients (87%) who underwent these procedures on an outpatient basis : arteriographies (221) or percutaneous transluminal angioplasties (76) and a few intravenous studies (9). The results revealed a high degree of satisfaction from the patients (98%), no major complications and a very low incidence of minor complications (3%).

[Percutaneous transluminal angioplasty of peripheral arteries: past, present and future]. / Angioplastie transluminale percutanée des artères périphériques: passé, présent et futur.

Balloon percutaneous transluminal angioplasty (PTA) has been described in 1974 and has since been considerably refined with the improvement of balloon catheters, guide wires and radiology equipment. Laser and other mechanical recanalization devices have not hold to their initial promises. Clinical and angiographic indications for PTA have been better defined over the years, resulting in excellent clinical successes with low morbidity and very low mortality. PTA has become an almost painless procedure and may be done on an outpatient basis. It is considered as the treatment of first choice in suitable patients.

[Superior venacavography at the patient's bedside]. / La phlébographie cave supérieure au lit du patient.

Acute onset of superior vena cava syndrome in critically ill patients, hours after cardiac surgery, needs angiographic documentation without delay in order to proceed with appropriate treatment. Bedside diagnostic venacavography was done for two patients in the surgical intensive care unit with a simple and safe method using a central venous catheter already in place.

Abdominal aortic angioplasty: a case report with angiographic follow-up.

Two women with typical clinical and angiographic findings of aorto-iliac occlusive disease underwent a successful percutaneous transluminal angioplasty of a severe stenosis of the lower abdominal aorta. One of them in whom control aortograms provide information on the mechanism of balloon angioplasty is reported here.

Percutaneous transluminal angioplasty of the lower abdominal aorta.

Percutaneous transluminal angioplasty (PTA) of the lower abdominal aorta was performed in 14 patients aged 29-66 years (mean, 50). The disease was largely isolated to the distal aorta in this group. There were 13 women and 1 man; all were heavy smokers. Initial success, defined as improved or subsided clinical symptoms, improved ankle/arm indices, and improved angiogram, was achieved in all but one patient who thrombosed at the puncture site. At a mean follow-up period of 16 months (range, 1-58), a persistent beneficial effect was maintained in all patients. These results suggest that PTA is a safe alternative to surgery in patients with signs and symptoms of aortoiliac disease secondary to a significant but short stenotic segment of the lower abdominal aorta.

A device to measure roentgenographic structures.

A simple device and a nomogram are presented to permit rapid, accurate measurement of structures shown on roentgenograms. The arrangement is designed specifically for measurement of coronary vessels, but it can be adapted to other structures.