Graft control by transit time flow measurement and intraoperative angiography in coronary artery bypass surgery.

BACKGROUND: The aim of this study was to compare the relationship between intraoperative transit time flow measurements and angiographic findings with long-term graft patency in 72 patients who underwent coronary artery bypass surgery. METHODS: Transit time flow measurements with recording of mean flow and pulsatility indexes were performed after completion of the anastomoses. Coronary angiography was performed on-table while the patients were still in general anesthesia, and then at follow-up three months and 12 months after surgery. Based on angiography, the grafts were graded as type A (fully patent), type B (having more than 50% diameter reduction), or type O (occluded). RESULTS: Of the 67 left internal mammary artery (LIMA) grafts, 51 (76%) were type A on-table, 14 (21%) were type B, and two (3%) were type O. Of the 57 saphenous vein grafts, 49 (86%) were type A, 7 (12%) were type B, and one (2%) was type O. For both LIMA and vein grafts, there were no differences in flow (p = 0.69 and 0.47, respectively) or pulsatility index (p = 0.79 and 0.83) between type A and B. There were also no differences in flow (p = 0.37 and 0.7) or pulsatility index (p = 0.37 and 0.24) between type B on-table that either normalized or persisted occluded at the follow-up. Transit time flow measurement failed to detect an occluded LIMA graft as shown by intraoperative angiography. CONCLUSIONS: Blood flow measurements performed intraoperatively could not identify significant lesions in arterial or vein grafts, and could not predict graft patency. We have become cautious in interpreting flow measurements alone and combine blood flow recordings with intraoperative angiography in the assessment of graft quality.

Restenosis and clinical outcome in patients treated with amlodipine after angioplasty: results from the Coronary AngioPlasty Amlodipine REStenosis Study (CAPARES).

OBJECTIVES: Our intent was to investigate the effect of the dihydropyridine calcium channel blocker amlodipine on restenosis and clinical outcome in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Amlodipine has sustained vasodilatory effects and relieves coronary spasm, which may reduce luminal loss and clinical complications after PTCA. METHODS: In a prospective, double-blind design, 635 patients were randomized to 10 mg of amlodipine or placebo. Pretreatment with the study drug started two weeks before PTCA and continued until four months after PTCA. The primary angiographic end point was loss in minimal lumen diameter (MLD) from post-PTCA to follow-up, as assessed by quantitative coronary angiography (QCA). Clinical end points were death, myocardial infarction, coronary artery bypass graft surgery and repeat PTCA (major adverse clinical events). RESULTS: Angioplasty was performed in 585 patients (92.1%); 91 patients (15.6%) had coronary stents implanted. Follow-up angiography suitable for QCA analysis was done in 236 patients in the amlodipine group and 215 patients in the placebo group (per-protocol group). The mean loss in MLD was 0.30 +/- 0.45 mm in the amlodipine group versus 0.29 +/- 0.49 mm in the placebo group (p = 0.84). The need for repeat PTCA was significantly lower in the amlodipine versus the placebo group (10 [3.1%] vs. 23 patients [7.3%], p = 0.02, relative risk ratio [RR]: 0.45, 95% confidence interval [CI]: 0.22 to 0.91), and the composite incidence of clinical events (30 [9.4%] vs. 46 patients (14.5%), p = 0.049, RR: 0.65, CI: 0.43 to 0.99) within the four months follow-up period (intention-to-treat analysis). CONCLUSIONS: Amlodipine therapy starting two weeks before PTCA did not reduce luminal loss, but the incidence of repeat PTCA and the composite major adverse clinical events were significantly reduced during the four-month follow-up period after PTCA with amlodipine as compared with placebo.

Preservation of renal function by percutaneous transluminal angioplasty in ischaemic renal disease.

BACKGROUND: The purpose of this study was to evaluate the effects of percutaneous transluminal renal angioplasty (PTRA) on preservation of renal function in patients with bilateral renal artery stenoses or stenosis of the artery of one functioning kidney. METHODS: A total of 227 PTRAs of 223 stenoses in 135 patients were performed from 1982 to 1993 in a single centre and retrospectively reviewed. The number of PTRAs per patient was 1.7, range 1-6. Angiographical follow-up was performed in 77%, 120+/-82 days after the first PTRA and 273+/-345 days after the last PTRA. Follow-up of serum creatinine and blood pressure was performed in 85% after 414+/-558 days. Long-term follow-up was performed for dialysis, surgical revascularization, renal transplantation and death, mean follow-up 8.8 years, range 5.5-14.8. RESULTS: The immediate technical success was 90%, and another 5% were improved. The primary patency rate per patient was 43% and the secondary patency rate 64%. Improved renal function was achieved in 23% of the patients, stabilized in 56% and failed in 21%. Stabilized or improved function was higher when baseline serum creatinine was < or =250 micromol/l (85%) than >250 micromol/l (60%). Three of 99 (3%) patients with creatinine < or =250 micromol/l started dialysis during follow-up (41 days, 7.4 and 8 years), as did 13 of 36 (36%) patients with creatinine >250 micromol/l. Blood pressure and the number of antihypertensive drugs decreased in patients with creatinine < or =250 micromol/l, but was unchanged in those with creatinine >250 micromol/l. The 5-year survival rates were 84, 66 and 17% for patients with creatinine <125 micromol/l, 125-250 micromol/l and >250 micromol/l, respectively. Twelve patients (9%) experienced complications, including two deaths. CONCLUSIONS: Our study shows that PTRA improved or preserved the renal function in most patients with normal to moderately impaired renal function. Close follow-up and possibly re-intervention are necessary to obtain satisfactory clinical and angiographical result.

Percutaneous transluminal renal artery angioplasty using the coaxial technique. Ten years of experience from 591 procedures in 419 patients.

PURPOSE: To evaluate the angiographic and clinical results of all percutaneous transluminal renal angioplasties (PTRAs) performed at one centre in Norway since the introduction of the method. Most of the PTRAs were performed with the coaxial technique (guiding-catheter-assisted angioplasty). MATERIAL AND METHODS: In 419 patients, 595 PTRAs of 552 stenoses were performed from 1982 to 1993. The cases included 295 patients with arteriosclerotic vascular disease (AVD), 49 with fibromuscular dysplasia (FMD), and 74 transplantation patients (TX). Angiographic and clinical follow-up were undertaken. RESULTS: Initial angiographic success was obtained in 92% of the patients and another 3% improved. The rates of immediate success were 92%, 98% and 84% for AVD, FMD and TX respectively. The corresponding rates for primary patency were 57%, 67% and 54%, and for secondary patency (after 1 to 6 angioplasties) 77%, 93% and 64%. Lower long-term results were obtained for: recanalized vessels; long lesions; bifurcation stenoses; stenoses in patients with abdominal aortic aneurysm; smaller vessels; and segmental branches in native and TX kidneys. Of 252 patients with hypertension, 8% were cured and another 58% improved. Of 215 patients with reduced renal function, 38% were normalized or improved and 42% unchanged. Major complications including 2 deaths were seen in 2.9% of the procedures and other complications in 4.7%. CONCLUSION: PTRA with a guiding catheter can be performed in most patients with a high success rate and a low complication rate. This study points to two major problems with PTRA: the high restenosis rate and the low response to treatment of hypertension. The careful selection of patients for PTRA is important for increasing the success rate, and follow-up to detect restenosis is mandatory.

Minimally invasive direct coronary artery bypass grafting without cardiopulmonary bypass in combination with intraoperative percutaneous transluminal coronary angioplasty for palliative coronary revascularization in a heart transplant recipient.

The use of minimally invasive direct coronary artery bypass grafting without cardiopulmonary bypass in combination with intraoperative percutaneous transluminal coronary angioplasty for myocardial revascularization in a heart transplant recipient is reported.

Retrograde internal mammary artery as coronary bypass. A prospective study with postoperative angiographic evaluation.

Although the internal mammary artery (IMA) as a coronary graft offers better long-term patency than the saphenous vein, a factor limiting its use has been the length of the artery's pedicle. In an attempt to overcome this limitation, we evaluated the use of retrograde right IMA in a prospective study. In ten patients scheduled for routine coronary artery bypass surgery, bilateral IMA grafting was used, the left IMA in routine fashion, but the right IMA dissected from the level of the first rib, cut there and placed as an inverted graft. Three months postoperatively the patients were clinically evaluated with stress exercise test (n = 10) and coronary angiography (n = 9). No patient had recurrence of angina. Angiography revealed patency of the retrograde right IMA graft in six of nine patients. On the basis of these data we do not recommend routine use of retrograde IMA.

Intraoperative angiography in minimally invasive direct coronary artery bypass grafting.

Intraoperative angiography in minimally invasive direct coronary artery bypass grafting without cardiopulmonary bypass and in hybrid procedures is reported. Twelve procedures were performed in a specially designed surgical-radiologic suite with a cross-disciplinary organization. In 2 patients the anastomosis was successfully revised on the basis of angiographic findings. In 4 of the 12 patients anastomosis of the left internal mammary artery to the left anterior descending coronary artery performed as a minimally invasive direct coronary artery bypass grafting procedure was combined with percutaneous transluminal coronary angioplasty of lesions in other coronary vessels in the same session. Intraoperative angiography allows a reliable diagnosis of an anastomosis or graft failure and prompt and reliable correction, and it allows the combination of minimally invasive direct coronary artery bypass grafting and angioplasty in one session.

[Embolization of congenital pulmonary arteriovenous malformations]. / Embolisering av medfødte arteriovenøse malformasjoner i lungene.

Patients with arteriovenous pulmonary malformations are at risk of developing secondary brain disease such as transient ischemic attacks, strokes or abscesses. Lethal haemothorax and haemoptysis also occur. 12 of 14 malformations in five patients were treated using a total of eight procedures. One patient experienced a transient unilateral hemiparesis, otherwise no complications occurred. None of the 43 deployed occlusion coils was lost through the fistulas. Complete occlusion was achieved in all lesions where coils could be placed in a stable position. One patient suffered a minor recurrence. The use of interlocking detachable coils (IDC) which can be retracted or repositioned prior to full deployment is recommended.

Coronary angioplasty using a low osmolar nonionic contrast medium. A retrospective angiographic and clinical evaluation.

This study was performed to investigate the occurrence of acute angiographic and clinical complications following PTCA using a low osmolar nonionic contrast medium. Five hundred consecutive PTCA procedures were analyzed retrospectively. The incidence of acute in laboratory complications during PTCA as well as complications occurring during the hospital stay 24 to 48 hours after the procedure were recorded. Occlusion of the dilated artery or a side branch was observed in 19 (3.8%) of the procedures, major dissection in 34 (6.8%), and thrombus in 14 (2.8%). One patient died, 6 (1.2%) required emergency coronary artery bypass grafting (CABG), 4 (0.8%) required an emergency PTCA, and 7 (1.4%) suffered myocardial infarction (MI). Our results show that angiographic findings of thrombus, major dissection and occlusion were serious conditions that related to the clinical complications MI, emergency CABG and re-PTCA. Patients with unstable angina were risk patients for both angiographic and clinical complications. Low rates of intraarterial thrombus formation and coronary artery occlusion indicate good angiographic technique and anticoagulant and antiplatelet medication.

Cerebral thromboembolic complications associated with the use of a nonionic contrast medium in coronary angiography.

Cerebrovascular complications were registered in 11 patients (0.21%) of 5,339, consecutively submitted to coronary angiography with the nonionic contrast medium iohexol (Omnipaque). Six of the patients had diseases predisposing them to thromboembolic complications, 3 of whom earlier had symptoms of cerebral stroke. Excluding these 6, the incidence of cerebral thromboembolic events was 0.10% in patients with no predisposing diseases. Precise catheterization technique and some anticoagulation and antiplatelet activity therapy are definite precautions against these complications, while the role of the contrast medium is still debated.

[Endarterectomy of left coronary arteries. An angiographic follow-up study]. / Endarterektomi av venstre koronararteries grener. En etterundersøkelse med angiografi.

From January 1989 to December 1993, 25 patients underwent endarterectomy on the left coronary artery system. Eight of the patients had concurrent endarterectomy of the right coronary artery. The operative mortality consisted of one high-risk patient who died from an intraoperative myocardial infarction. Two patients developed non-fatal perioperative infarction. The follow-up period averaged 27 months (range 4-58 months). At follow-up one patient was lost for evaluation owing to unexpected sudden death, no patients had experienced myocardial infarction, 17 patients (74%) were free of angina, two patients were in NYHA class I and four in NYHA class II. All patients showed an improvement in relation to their preoperative condition. Two asymptomatic patients refused recatheterization, while 21 patients had a control angiographic study. 25 of 34 grafts to endarterectomized vessels were open (patency 74%) compared with 41 of 45 grafts to non-endarterectomized arteries (patency 91%). We find the angiographic and functional results acceptable and they should be acknowledged with reference to patients with diffuse distal coronary artery disease, many of whom would otherwise be considered inoperable.

[Catheter therapy of coronary disease]. / Kateterbehandling av koronarsykdom.

Percutaneous transluminal coronary angioplasty (PTCA) with balloon catheters is a well established invasive treatment for coronary artery disease. The high frequency of restenosis has promoted the development of new catheters, with different techniques for removing the plaques from the coronary arteries. Until now the rate of restenosis using balloon angioplasty and new atherectomy catheters has not declined. Our experience of these techniques is discussed and compared with the experiences described in the literature. The use of stents seems to be a major step forward, leading to fewer restenoses and emergency bypass operations.

[Catheter treatment of renal artery stenoses]. / Kateterbehandling av nyrearteriestenoser.

Percutaneous transluminal renal artery angioplasty (PTRA) is an alternative to treatment with drugs and surgery for renovascular hypertension and uremia. The procedure is technically successful in more than 90% of the patients. Renovascular hypertension is cured or improved in nearly 2/3 of the patients. Uremia is cured in 50%, and in another third the kidney function is stabilized. The frequency of restenosis is high, especially for ostial lesions. Therefore, clinical and angiographic follow-up is recommended, so as to redilate when restenosis is present. Introduction of stents probably reduces the frequency of restenosis in the ostial lesions.

[Are the results of thallium scintigraphy and coronary angiography equivalent? An evaluation of thallium scintigraphies performed at Vestfold Central Hospital]. / Er det samsvar mellom resultatene av thalliumscintigrafi og koronar angiografi? En evaluering av thalliumscintigrafiundersøkelser utført ved Vestfold sentralsykehus.

The value of exercise-redistribution thallium-201 perfusion scintigraphy (SPECT; single photon emission computed tomography) in the diagnosis of coronary artery disease was evaluated in 23 patients (one patient tested twice) who were subsequently submitted to coronary angiography. Reversible perfusion defects indicating myocardial ischemia were found in 22 patients, of whom 18 had angiographically significant coronary artery stenoses. Two patients had negative thallium scans, one had a normal angiogram and one had single vessel disease. Thus 18 of 19 patients with angiographically verified coronary heart disease had a positive thallium scan. The majority of patients with left main stenosis and triple vessel disease had scintigraphic evidence of double or triple vessel disease. The scintigraphic method identified the correct anatomical localization in 73% of the angiographically verified coronary artery stenoses. In conclusion, a positive exercise-redistribution thallium scan had a high predictive value in the diagnosis of coronary artery disease, whereas its value in estimating the number and localization of stenoses was more limited.

Surgical intervention following failed percutaneous coronary angioplasty.

Percutaneous transluminal coronary angioplasty (PTCA) was performed on 725 occasions at the National Hospital of Norway in 1981-1990. Acute surgical intervention was necessary within 24 hours after PTCA in 15 cases, on indications that included coronary artery dissection (8 cases) and acute thrombotic occlusion (5). Electrocardiographic signs of ischemia were present in 11 patients with anginal pain, while two had severe angina but normal electrocardiogram. Two patients had a non-ischemic indication for surgery. Despite surgery, ten of the 15 patients had acute myocardial infarction. One of the ten died. At follow-up nine of 12 patients were free from angina and three had recurrent symptoms.

Occurrence and management of fractured peripheral catheters in CSF shunts.

A series of 716 children underwent 2065 cerebrospinal fluid shunt procedures. Shunt failure due to fracture of the peripheral drain occurred 60 times, 38 times in ventriculo-atrial and 22 times in ventriculo-peritoneal shunts. The break occurred most commonly 2-4 cm above the neck incision in cardiac and just cephalad to the clavicle in abdominal drains. Fifty-nine ruptures occurred in Pudenz catheters (which were used in 82% of the shunts) and 1 occurred in a Holter drain (used in 17%). The fractured atrial catheters remained in situ (5/38) or were dislodged into the right cardiac ventricle (14/38), pulmonary arteries (9/38), right atrium (5/38) or hepatic veins (3/38). Two of the ruptured drains could not be located. Removal by a percutaneous transvascular snare technique was attempted in 27 cases and was successful in 24.

Restenosis after percutaneous transluminal coronary angioplasty.

Restenosis after percutaneous transluminal coronary angioplasty was demonstrated in 61 (29%) of 210 successfully treated patients. Mostly it occurred within 4 months after treatment and in arteries less than 3 mm in diameter. Careful clinical follow-up is therefore particularly important early after angioplasty of smaller arteries. Redilation can be performed without increased risk of restenosis.

Hemodynamic evaluation of the CarboMedics prosthetic heart valve in the aortic position: comparison of noninvasive and invasive techniques.

Seventy-three patients with a CarboMedics aortic bileaflet valve prosthesis were examined by Doppler ultrasonography, and 27 of them were also assessed by transseptal catheterization. The ultrasonic mean systolic gradient was 17.1 +/- 5.6 mm Hg for valve size 19 mm, falling gradually with increasing valve size to 6.8 +/- 2.5 mm Hg for size 27 mm. The catheter mean systolic gradient was consistently smaller than the ultrasonic gradient (4.3 +/- 4.8 mm Hg), but Tobit regression analysis showed a significant association between the two methods. In all patients both methods revealed negligible to small amounts of retrograde leakage, which is assumed to be a normal finding for this valve. The effective flow areas of the valves calculated from the ultrasonic data were similar to the in vitro calculated flow areas. The hemodynamic potential of this valve is therefore completely utilized in vivo. The effective orifice area corrected for body surface area increased with increasing valve size, which demonstrates a moderate valve-patient mismatch.

Single lung transplantation. Surgical experiences with the first seven patients.

Seven single lung transplants are reported. The patients were severely disabled and oxygen dependent below sixty years of age with a poor prognosis. Diagnosis were alfa 1-antitrypsin deficiency (3), sarcoidosis (3) and idiopathic emphysema (1). Multiorgan-harvesting including six hearts, was performed in local or distant hospitals (3). Partial cardiopulmonary bypass simplified transplantation. The surgical procedure was modified with a direct transpericardial approach. Soft tissue wrapping by a vascularized pedicle secured the bronchial anastomosis. The four drug immunosuppressive regimen included cyclosporin A, azathioprine, steroids and antithymocyte globulin. Primary graft function was excellent. Six patients survived the postoperative period and are alive 5-19 months post transplant. Transbronchial biopsies and lung function studies have been helpful in detecting pulmonary rejections. Patient rehabilitation is satisfactory in most patients with improvement in physiologic parameters.