Comparison of two three-dimensional gated SPECT methods with thallium in patients with large myocardial infarction

BACKGROUND

Two different commercially available gated single photon emission computed tomography (GSPECT) methods were compared in a population of patients with a major myocardial infarction.

METHODS

Rest thallium GSPECT was performed with a 90-degree dual-detector camera, 4 hours after injection of thallium-201 (Tl-201; 185 MBq) in 43 patients (mean age, 62+/-12 years) with a large myocardial infarction (mean defect size, 33%+/-16%). End-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular ejection fraction (LVEF) were calculated by using QGS (Cedars Sinai) and MultiDim (Sopha Medical Vision International, Buc, France). Images were reconstructed by using a 2.5 zoom and a Butterworth filter (order, 5; cut-off frequency, 0.20). LVEF was calculated in all patients by using equilibrium radionuclide angiocardiography (ERNA). EDV, ESV, and LVEF were also measured by using left ventriculography (LVG).

RESULTS

Compared with LVG, QGS underestimated LVEF by means of an underestimation of mean EDV. MultiDim overestimated EDV and ESV. GSPECT EDV and ESV overestimation was demonstrated by means of Bland-Altman analysis to increase with left ventricular volume size (P<.05). The difference between LVG and GSPECT volumes was demonstrated by means of regression analysis to be correlated with infarction size. This effect was particularly important with MultiDim (P<.0001).

CONCLUSION

In Tl-201 GSPECT, LVEF and volume measurements will vary according to the type of software used.

A comparison of systematic stenting and conventional balloon angioplasty during primary percutaneous transluminal coronary angioplasty for acute myocardial infarction. STENTIM-2 Investigators

OBJECTIVES

In a multicenter, randomized trial, systematic stenting using the Wiktor stent was compared to conventional balloon angioplasty with provisional stenting for the treatment of acute myocardial infarction (AMI).

BACKGROUND

Primary angioplasty in AMI is limited by in-hospital recurrent ischemia and a high restenosis rate.

METHODS

A total of 211 patients with AMI <12 h from symptom onset, with an occluded native coronary artery, were randomly assigned to systematic stenting (n = 101) or balloon angioplasty (n = 110). The primary end point was the binary six-month restenosis rate determined by core laboratory quantitative angiographic analysis.

RESULTS

Angiographic success (Thrombolysis in Myocardial Infarction [TIMI] flow grade 3 and residual diameter stenosis <50%) was achieved in 86% of the patients in the stent group and in 82.7% of those in the balloon angioplasty group (p = 0.5). Compared with the 3% cross-over in the stent group, cross-over to stenting was required in 36.4% of patients in the balloon angioplasty group (p = 0.0001). Six-month binary restenosis (> or = 50% residual stenosis) rates were 25.3% in the stent group and 39.6% in the balloon angioplasty group (p = 0.04). At six months, the event-free survival rates were 81.2% in the stent group and 72.7% in the balloon angioplasty group (p = 0.14), and the repeat revascularization rates were 16.8% and 26.4%, respectively (p = 0.1). At one year, the event-free survival rates were 80.2% in the stent group and 71.8% in the balloon angioplasty group (p = 0.16), and the repeat revascularization rates were 17.8% and 28.2%, respectively (p = 0.1).

CONCLUSIONS

In the setting of primary angioplasty for AMI, as compared with a strategy of conventional balloon angioplasty, systematic stenting using the Wiktor stent results in lower rates of angiographic restenosis.

[Percutaneous mitral commissurotomy by metallic dilator. Multicenter experience with 500 patients]

A clinical investigation has been conducted since January 1996 with a new valve dilator for percutaneous treatment of mitral stenosis: metallic commissurotome. This new technique is based on the principle of surgical commissurotome but, in its mechanism of action, differs from the usual techniques with balloon catheters. It also offers the unique possibility for multiple utilizations of the same device after resterilization. This article reports a multicenter international investigation involving 500 patients, mean age of 34 +/- 13 years, with a isolated mitral stenosis and an echography score of 7.7 +/- 1.9. Our technique has been feasible in 489 cases (98%) with a success rate (mitral area > 1.5 cm2 without MR > grade 2) of 93%. The transmitral gradient has diminished from 20 +/- 8 mmHg to 4 +/- 3 mm Hg and the mitral area (assessed by planimetry at 24 hrs) has increased from 0.91 +/- 0.20 to 2.12 +/- 0.34 cm2. Complications were uncommon (13 patients: 2.6%) and consisted in 6 tamponades, 5 mitral insufficiencies (one patient required an emergency valve replacement) and 2 neurological transient accidents. The outcomes of this clinical investigation appear most encouraging and at least comparable to those being reported with the commonly used techniques. The most serious complications appear to be closely related to the level of experience with this technique. Considering the possibility to reutilize the metal segments of the apparatus, this technique notably reduces the cost of the procedure per patient and it represents a significant benefit in countries with limited resources.

Effect of temporal sampling on evaluation of left ventricular ejection fraction by means of thallium-201 gated SPET: comparison of 16- and 8-interval gating, with reference to equilibrium radionuclide angiography

Gated myocardial single-photon emission tomography (SPET) allows the evaluation of left ventricular ejection fraction (LVEF), but temporal undersampling may lead to systolic truncation and ejection fraction underestimation. The aim of this study was to evaluate the impact of temporal sampling on thallium gated SPET LVEF measurements. Fifty-five consecutive patients (46 men, mean age 62+/-12 years) with a history of myocardial infarction (anterior 31, inferior 24) were studied. All patients underwent equilibrium radionuclide angiography (ERNA) and gated SPET 4 h after a rest injection of 185 MBq (5 mCi) of thallium-201 using either 8-interval (group 1, n=25) or 16-interval gating (group 2, n=30). In group 2, gated SPET acquisitions were automatically resampled to an 8-interval data set. Projection data were reconstructed using filtered back-projection (Butterworth filter, order 5, cut-off 0.20). LVEF was then calculated using commercially available software (QGS). A higher correlation between gated SPET and ERNA was obtained with 16-interval gating (r=0.94) compared with the resampled data set (r=0.84) and 8-interval gating (r=0.71). Bland-Altman plots showed a dramatic improvement in the agreement between gated SPET and ERNA with 16-interval gating (mean difference: -0.10%+/-5%). Using multiple ANOVA, temporal sampling was the only parameter to influence the difference between the two methods. When using 8-interval gating, gated SPET LVEF was overestimated in women and underestimated in men (ERNA minus gated SPET = -4.0%+/-9.6% in women and 3.6%+/-7.6% in men, P=0.01). In conclusion, 16-interval thallium gated SPET offered the best correlation and agreement with ERNA, and should be preferred to 8-interval gated acquisition for LVEF measurement.

Thallium-gated SPECT in patients with major myocardial infarction: effect of filtering and zooming in comparison with equilibrium radionuclide imaging and left ventriculography

The effect of filtering and zooming on 201TI-gated SPECT was evaluated in patients with major myocardial infarction.

METHODS

Rest thallium (TI)-gated SPECT was performed with a 90 degrees dual-head camera, 4 h after injection of 185 MBq 201TI in 32 patients (mean age 61 +/- 11 y) with large myocardial infarction (33% +/- 17% defect on bull's eye). End diastolic volume (EDV), end systolic volume (ESV) and left ventricular ejection fraction (LVEF) were calculated using a commercially available semiautomatic validated software. First, images were reconstructed using a 2.5 zoom, a Butterworth filter (order = 5) and six Nyquist cutoff frequencies: 0.13 (B5.13), 0.15 (B5.15), 0.20 (B5.20), 0.25 (B5.25), 0.30 (B5.30) and 0.35 (B5.35). Second, images were reconstructed using a zoom of 1 and a Butterworth filter (order = 5) (cutoff frequency 0.20 [B5.20Z1]) (total = 32 x 7 = 224 reconstructions). LVEF was calculated in all patients using equilibrium radionuclide angiocardiography (ERNA). EDV, ESV and LVEF were measured with contrast left ventriculography (LVG).

RESULTS

LVEF was 39% +/- 2% (mean +/- SEM) for ERNA and 40% +/- 13% for LVG (P = 0.51). Gated SPECT with B5.20Z2.5 simultaneously offered a mean LVEF value (39% +/- 2%) similar to ERNA (39% +/- 2%) and LVG (40% +/- 3%), optimal correlations with both ERNA (r = 0.83) and LVG (r = 0.70) and minimal differences with both ERNA (-0.9% +/- 7.5% [mean +/- SD]) and LVG (1.1% +/- 10.5%). As a function of filter and zoom choice, correlation coefficients between ERNA or LVG LVEF, and gated SPECT ranged from 0.26 to 0.88; and correlation coefficients between LVG and gated SPECT volumes ranged from 0.87 to 0.94. There was a significant effect of filtering and zooming on EDV, ESV and LVEF (P < 0.0001). Low cutoff frequency (B5.13) overestimated LVEF (P < 0.0001 versus ERNA and LVG). Gated SPECT with 2.5 zoom and high cutoff frequencies (B5.15, B5.20, B5.25, B5.30 and B5.35) overestimated EDV and ESV (P < 0.04) compared with LVG. This volume overestimation with TI-gated SPECT in patients with large myocardial infarction was correlated to the infarct size. A zoom of 1 underestimated EDV, ESV and LVEF compared with a 2.5 zoom (P < 0.02).

CONCLUSION

Accurate LVEF measurement is possible with TI-gated SPECT in patients with major myocardial infarction. However, filtering and zooming greatly influence EDV, ESV and LVEF measurements, and TI-gated SPECT overestimates left ventricular volumes, particularly when the infarct size increases.

Percutaneous mechanical mitral commissurotomy with a newly designed metallic valvulotome: immediate results of the initial experience in 153 patients

BACKGROUND

Percutaneous balloon valvotomy has become a common treatment of mitral stenosis, but the cost of the procedure remains a limitation in countries with restricted financial resources, leading to a frequent reuse of the disposable catheters. To overcome this limitation, a reusable metallic valvotomy device has been developed with the goals of both improving the mitral valvotomy results and decreasing the cost of the procedure.

METHODS AND RESULTS

The device consists of a detachable metallic cylinder with 2 articulated bars screwed onto the distal end of a disposable catheter whose proximal end is connected to an activating pliers. By the transseptal route, the device is advanced across the valve over a traction guidewire. Squeezing the pliers opens the bars up to a maximum extent of 40 mm. The clinical experience consisted of 153 patients with a broad spectrum of mitral valve deformities. The procedure was successful in 92% of cases and resulted in a significant increase in mitral valve area, from 0.95+/-0.2 to 2. 16+/-0.4 cm2. No increase in mitral regurgitation was noted in 80% of cases. Bilateral splitting of the commissures was observed in 87%. Complications were 2 cases of severe mitral regurgitation (1 requiring surgery), 1 pericardial tamponade, and 1 transient cerebrovascular embolic event. In this series, the maximum number of consecutive patients treated with the same device was 35.

CONCLUSIONS

The results obtained with this new device are encouraging and at least comparable to those of current balloon techniques. Multiple uses after sterilization should markedly decrease the procedural cost, a major advantage in countries with limited resources and high incidence of mitral stenosis.

Relation between serum cardiac troponin I values and severity of clinical, electrocardiographic and quantitative angiographic features in unstable angina

This study sought to find out a correlation, if any, between serum cardiac troponin I values and extent and severity of coronary artery disease in patients with unstable angina. Eighty patients with unstable angina and normal serum creatine kinase values were studied and a comparative evaluation of serum cardiac troponin I values with clinical findings, electrocardiography, quantitative coronary angiography and follow-up events was performed. Among 80 patients, 34 (43%) had cardiac troponin I values of 0.6 microgram/L or higher (group I) and 46 (57%), below 0.6 microgram/L (group II). The mean cardiac troponin I in group I was 2.6 +/- 1.7 micrograms/L and 0.2 +/- 0.1 microgram/L in group II. The patients in group I had more type C lesions, frequent triple vessel and left main coronary artery involvement, and higher mean percentage diameter stenosis in the coronary arteries than those in group II. Early follow-up showed that more patients in group I required procedures earlier (including PTCA and CABG) than those from group II. Mid-term follow-up (9.5 +/- 4 months) data also showed greater occurrence of cardiac events (i.e. myocardial infarction and the increased need of PTCA) in group I. Patients with elevated cardiac troponin I more often experienced Braunwald's class III (A and B) unstable angina associated with presence of marked ST-T changes on the electrocardiography than those from group II. Our study suggests elevated values of serum cardiac troponin I to be evenly associated with the severity and extent of coronary lesions, clinical severity of unstable angina and marked electrocardiographic changes. Follow-up results confirm the potential value of this marker in predicting the course of coronary artery disease.

Clinical and angiographic results of stenting for long coronary arterial atherosclerotic lesions

A prospective registry of 187 patients who underwent percutaneous coronary angioplasty with attempted long NIR stent delivery was performed. A successful stent delivery was achieved in 93% of cases with a low rate of major cardiovascular events, and 6-month follow-up showed low rates of clinical events, new revascularization procedures, and angiographic restenosis.

[Immediate and 6-month results of balloon angioplasty in the treatment of intra-stent restenosis in symptomatic patients]

The aim of this prospective study was to assess the clinical and angiographic immediate and 6 month results of balloon angioplasty in intra-stent restenosis. Quantitative angiographic analysis (Philips DCI) was performed before and after implantation of the stent, before and after angioplasty for restenosis and at the 6 month control procedure. The study included 59 patients with 65 stents with an intra-stent restenosis. Restenosis was diffuse (10 mm) in 70% of cases, and focal in 30% of cases. The length of the stent was 16 +/- 7 mm (Palmaz-Schatz: 58%). The diameter of the balloon used for angioplasty was 2.9 +/- 0.4 mm and the maximal inflation pressure was 10 +/- 3 bars. The success rate was 100% with no complications. Control coronary angiography was performed in 92% of patients after an average of 5.9 months. The angiographic restenosis rate was 54% and revascularisation was required in 21 patients (36%). The restenosis rate was higher in cases of diffuse intra-stent restenosis (64%) than in focal restenosis (29%), p = 0.02. The authors conclude that balloon angioplasty for intra-stent restenosis is safe and carries a high success rate. Nevertheless, the angiographic restenosis rate at 6 months seems to be higher, especially in cases of diffuse restenosis.

Primary stenting of de novo lesions in small coronary arteries: a prospective, pilot study

Technical advancement and new anti-thrombotic regimens have recently shown so much improvement in the results of coronary stenting that the conventional contra-indication for stenting in small coronary arteries (<3 mm) needs to be revised. We undertook a prospective pilot study of elective Palmaz-Schatz stenting in de novo lesions located in coronary arteries of less than 3 mm diameter. Fifty consecutive patients (63 +/- 9 years) with stable (n = 38) and unstable angina (n = 12) were included. Philips-DCI quantitative coronary analysis was used to measure reference diameter, minimal lumen diameter and percent diameter stenosis before PTCA, after stenting and at 6-month angiographic follow-up study. All measurements were performed after intracoronary injection of nitroglycerin (300 microg). All patients received ticlopidine (250 mg/day) and aspirin (100 mg/day). The mean lesion length was 9 +/- 3 mm. The balloon size used for stent delivery was 2.75 mm in 30 patients and 2.5 mm in 20 patients and the mean balloon inflation pressure used for stent deployment was 12 +/- 2 atm. All stents were deployed successfully. In-hospital complications occurred in two patients, diagonal branch occlusion at day 2 requiring emergency PTCA in one and a hematoma at the femoral puncture site requiring surgery in the other. Major adverse cardiac event (MACE) rate remained 2% (nonfatal infarct in one). Follow-up angiography (n = 46, 92%) at 6 +/- 3 months showed a 30% restenosis rate. Target vessel revascularization (TVR) rate was 13%. We conclude that elective stenting in small coronary arteries is feasible and involves an acceptable risk of restenosis.

Balloon angioplasty for the treatment of coronary in-stent restenosis: immediate results and 6-month angiographic recurrent restenosis rate

OBJECTIVES

The purpose of this prospective study was to evaluate the immediate results and the 6-month angiographic recurrent restenosis rate after balloon angioplasty for in-stent restenosis.

BACKGROUND

Despite excellent immediate and mid-term results, 20% to 30% of patients with coronary stent implantation will present an angiographic restenosis and may require additional treatment. The optimal treatment for in-stent restenosis is still unclear.

METHODS

Quantitative coronary angiography (QCA) analyses were performed before and after stent implantation, before and after balloon angioplasty for in-stent restenosis and on a 6-month systematic coronary angiogram to assess the recurrent angiographic restenosis rate.

RESULTS

Balloon angioplasty was performed in 52 patients presenting in-stent restenosis. In-stent restenosis was either diffuse (> or =10 mm) inside the stent (71%) or focal (29%). Mean stent length was 16+/-7 mm. Balloon diameter of 2.98+/-0.37 mm and maximal inflation pressure of 10+/-3 atm were used for balloon angioplasty. Angiographic success rate was 100% without any complication. Acute gain was lower after balloon angioplasty for in-stent restenosis than after stent implantation: 1.19+/-0.60 mm vs. 1.75+/-0.68 mm (p=0.0002). At 6-month follow-up, 60% of patients were asymptomatic and no patient died. Eighteen patients (35%) had repeat target vessel revascularization. Angiographic restenosis rate was 54%. Recurrent restenosis rate was higher when in-stent restenosis was diffuse: 63% vs. 31% when focal, p=0.046.

CONCLUSIONS

Although balloon angioplasty for in-stent restenosis can be safely and successfully performed, it leads to less immediate stenosis improvement than at time of stent implantation and carries a high recurrent angiographic restenosis rate at 6 months, in particular in diffuse in-stent restenosis lesions.

[Detection of myocardial viability by echocardiography with dobutamine infusion three weeks after myocardial infarction]

The aim of this study was to assess the value of low dose dobutamine (5 and 10 gammas/Kg/min) echocardiography for the detection of hibernating myocardium in an infarcted zone three weeks after the initial infarction. The authors studied 23 patients (18 men, 15 women) with an average age of 59 +/- 8 years before and 3 months after angioplasty of the culprit artery. Segmental wall motion was assessed semi-quantitatively by the criteria of the American Society of Echocardiography. All patients had regional contractile abnormalities under basal conditions and all underwent control coronary angiography at 3 months. Improvement of segmental wall motion with dobutamine predicted improvement after revascularisation with positive and negative predictive values of 95% and 85% respectively. The sensitivity and specificity of the test calculated in the usual manner were 83% and 96% respectively. In addition, assessment of diastolic function showed reduction of the isovolumic relaxation time with dobutamine only in patients with hibernating myocardium (120 +/- 30 ms decreasing to 114 +/- 29 ms with dobutamine, p < 0.02). Low dose dobutamine echocardiography therefore allows reliable non-invasive prediction of hibernating myocardium three weeks after infarction. The reduction of isovolumic relaxation time with dobutamine could be an additional argument in favour of the diagnosis.

[Percutaneous coronary angioscopy in the diagnosis of cardiac graft coronary disease: comparison with the results of angiography]

Coronary disease in cardiac transplant patients is a major factor in the limitation of long term survival. The aim of this study was to compare the results of angioscopy with those of coronary angiography performed systematically every 18 months in our center. Twenty-nine patients (31 angioscopies) were assessed 38 +/- 21 months after transplantation. The appearance observed by angioscopy were: 1) normal, 2) yellow pigmentation of the arterial surface, 3) elevated plaque < 50%, 4) elevated plaque > or = 50% stenosis. Angiography was: 1) normal, 2) iregularities of the lumen or < 50% stenosis, 3) > or = 50% stenosis. The films were viewed by two independent investigators. Angioscopy was performed on the left anterior descending artery (N = 35), the left circumflex (N = 24) and the right coronary artery (N = 9). One to three arterial segments were examined per vessel (total of 117 segments: average 3.8 segments per patient). Angioscopy was uniterpretable in 13/117 (11%) of cases. Of the 81 (78%) segments considered normal at coronary angiography, only 55 seemed normal at angioscopy (68%). Of the 23 segments considered to be abnormal at coronary angiography, all were also considered to be abnormal at angioscopy. The authors conclude that coronary angioscopy seems to be more sensitive than coronary angiography for the detection of coronary disease due to chronic rejection. Prospective studies are required to determine whether the infra-angiographic angioscopic lesions correspond to earlier stages of coronary disease of the cardiac graft.

A new treatment for severe pulmonary embolism: percutaneous rheolytic thrombectomy

BACKGROUND

The rheolytic thrombectomy catheter has been specially designed to remove intravascular thrombus from coronary and peripheral arteries. It demonstrates a practical application of Bernoulli's principle relating to a low-pressure zone in the region of a high-velocity jet. In this device, this effect is created by direct high-pressure saline jets located at the tip. Thrombus is drawn into this region and, because of the large pressure difference, undergoes mechanical thrombolysis due to the powerful mixing forces. The resulting microparticles are aspirated through the same catheter and removed from the body.

METHODS AND RESULTS

We report the use of this device in two patients presenting with severe pulmonary embolism and contraindications to thrombolytic therapy. The two procedures were successfully performed with an excellent immediate angiographic result at the site of the rheolytic thrombectomy. In both cases, the clinical improvement was maintained at follow-up with the same good angiographic result and a decrease to a normal level of the systolic pulmonary pressure.

CONCLUSIONS

This preliminary results suggest that this easy technical method may be useful in the treatment of life-threatening pulmonary embolism in patients with absolute contraindications to thrombolytic therapy. A larger cohort of patients is necessary to determine whether this treatment should be proposed as an alternative to the use of fibrinolytics in selected patients.

Angioscopic evaluation of rotational atherectomy followed by additional balloon angioplasty versus balloon angioplasty alone in coronary artery disease: a prospective, randomized study

OBJECTIVES

This study sought to compare, by angioscopy, the morphologic changes induced by rotational atherectomy, followed by additional angioplasty, with those observed after balloon angioplasty alone.

BACKGROUND

Rotational atherectomy and balloon angioplasty act by different mechanisms, which could explain the difference in morphologic changes induced by these two techniques.

METHODS

The study group included 50 patients with 50 lesions who were randomly assigned to undergo rotational atherectomy (n = 24) or balloon angioplasty (n = 26). Rotational atherectomy with a single burr (approximately equal to 70% of coronary diameter) was systematically followed by additional balloon angioplasty. Angioscopy was performed immediately after the procedure. Abnormal angioscopic findings were 1) flaps, graded from 1 to 3 (1 = intimal flap; 2 = flap protruding into < 50% of the lumen; 3 = flap protruding into > or = 50% of the lumen); 2) thrombi, graded from 1 to 3 (1 = flat deposits; 2 = protruding but nonocclusive thrombus; 3 = occlusive thrombus); 3) subintimal hemorrhage; 4) longitudinal dissection. The two groups were comparable for clinical and angiographic baseline data.

RESULTS

On angioscopy, flaps were observed less frequently after rotational atherectomy followed by additional balloon angioplasty (8 [33%] of 24 lesions) than after balloon angioplasty alone (14 [54%] of 26 lesions, p = 0.08) and were also less severe (grade 1 in 6 lesions, grade 2 in 2 and grade 3 in none vs. grade 1 in 4 lesions, grade 2 in 5 and grade 3 in 5). Longitudinal dissections were also significantly less frequent: one versus six (p = 0.05). There was no difference in the incidence of angioscopic thrombi (p = 0.16) or subintimal hemorrhage (p = 0.15), but the power to detect a significant difference was low for these variables (37% and 26%, respectively).

CONCLUSIONS

Rotational atherectomy followed by additional balloon angioplasty leads to fewer angioscopic dissections and a trend toward fewer intimal flaps than balloon angioplasty alone. However, our angioscopic differences did not lead to an outcome difference between the two groups.

[Primary treatment of left coronary artery diseases by percutaneous implantation of stents]

Left main coronary artery (LM) stenting has only been reported in bail-out situations or absolute contraindications so surgery. The authors report the immediate and midterm results of primary Palmaz-Schatz stent implantation in two young patients without contraindication to surgery. The first patient, 58 year-old, was admitted for unstable angina in October 1994. Coronary angiography showed an isolated severe ostial lesion of the LM. After conferring with the surgical team which remained on stand-by, angioplasty and stent implantation were performed with excellent results, no complications and no restenosis on angiographic controls at 3 and 12 months. The patient remained asymptomatic 24 months later. The second patient, 38 year-old, was admitted in June 1995 for unstable angina, and coronary angiography showed a severe isolated stenosis in the middle of a long and wide LM. Primary coronary stenting was also performed with excellent results, no complication and no restenosis on angiographic controls at 4 and 8 months. This patient was still asymptomatic 16 months after stenting. These excellent immediate and medium-term results are encouraging and suggest that this form of treatment might be extended to patients with an isolated whether primary LM stent implantation could become a suitable alternative to surgery in the future.

Adaptation to myocardial ischemia during coronary angioplasty demonstrated by clinical, electrocardiographic, echocardiographic, and metabolic parameters

It has been shown that brief episodes of myocardial ischemia can render the heart more resistant to a prolonged subsequent ischemic episode. This phenomenon, called "preconditioning," has been described in human beings during coronary angioplasty with the use of clinical, electrocardiographic (ECG), or metabolic parameters. The goal of this study was to assess this phenomenon further with the use of echocardiographic and metabolic parameters in addition to clinical and ECG parameters. Eighteen patients with isolated stenosis of the left anterior descending coronary artery and a normal left ventricular function were included. Angioplasty consisted of four consecutive balloon inflations. Sequential changes in clinical, ECG (intracoronary ECG), echocardiographic, and metabolic parameters of myocardial ischemia were compared between the first and the fourth balloon inflations. Improved tolerance to myocardial ischemia with repeated coronary occlusions was demonstrated by a significant reduction in the severity of angina, ST-segment elevation, wall motion abnormalities, and lactate production. This study confirms the adaptation of myocardial ischemia to repeated coronary occlusions through measurement of clinical, ECG, echocardiographic, and metabolic parameters.

Effects of prolonged sequential balloon inflations on results of coronary angioplasty

In percutaneous transluminal coronary angioplasty (PTCA), prolonged balloon inflations using perfusion balloon catheters have shown a higher procedural success rate and fewer in-hospital complications than short balloon inflations. However, perfusion balloons have well-recognized limits for routine use. This study assessed the effects of a prolonged cumulative occlusion time obtained with sequential balloon inflations using a routine balloon catheter, applicable to all lesions, and compared these results with those obtained with standard short balloon inflations. Three hundred ten lesions (in 289 patients) were randomized to either standard (3 to 5 inflations < or = 1 minute each; n = 161) or prolonged (3 to 5 inflations of 3 to 5 minutes each; n = 149) balloon inflations. Angiographic success (residual stenosis <50% and no dissection > or = D1) was assessed at the end of this "protocol" phase. Further dilatation was performed if required ("adjunctive" phase). Systematic repeat catheterization was scheduled 4 to 6 months later. Cumulative inflation time was 198 +/- 58 seconds in the "standard" group versus 782 +/- 303 seconds in the "prolonged" group. At the end of the protocol phase, the success rate was higher after prolonged than after standard dilatation (92% vs 80%; p <0.002), with less frequent dissections (14% vs 30%; p = 0.0009). At the end of the adjunctive phase, required for 12 patients in the prolonged group and 32 patients in the standard group (p = 0.003), results were comparable in the 2 groups and the restenosis rate was similar at 6 months. The prolonged cumulative occlusion time achieved with sequential balloon inflations using a routine balloon catheter improves the immediate results of PTCA. Repeat catheterization shows no effect of prolonged sequential inflations on the restenosis rate.

[Myocardial adaptation to ischemia. A study during repeated prolonged coronary occlusions in angioplasty]

Coronary angioplasty provides an ideal model for studying ischemic preconditioning in humans. Four coronary occlusions, each lasting 5.2 +/- 1.3 min, separated by 3 min of reperfusion, were performed during angioplasty of isolated stenosis of the left anterior descending artery of 18 patients with stable angina and normal left ventricular function. The ischaemia was evaluated and compared during the first and fourth coronary occlusion with the aid of clinical, electrocardiographic, echocardiographic and metabolic parameters. We analysed: 1) interval to chest pain and its intensity; 2) degree of ST change on the intracoronary electrocardiogram; 3) regional wall motion abnormalities on 2D echocardiography; 4) coefficient of myocardial lactate extraction. The results showed that during the fourth occlusion: chest pain occurred later (93 +/- 57 vs 60 +/- 49 s; p < 0.05) and ST elevation was less (0.69 +/- 0.5 vs 1.03 +/- 0.8; p < 0.05). During the fourth occlusion, there was a delay in appearance and a decrease in the regional wall motion abnormalities: anterior wall hypokinesia occurred later: 26 +/- 15 vs 19 +/- 19 s (p = 0.08). Akinesia observed in 10 patients out of 13 (77%) during the first occlusion, was only observed in 8 patients (62%) and dyskinesia, observed in 5 patients out of 13 (38%) during the first occlusion was not observed thereafter in any patient. The production lactate was less important during the fourth occlusion than during the first one: -3 +/- 17% vs -12 +/- 19% (p < 0.05). This study confirms that, in man, preconditioning allows myocardial adaptation to successive episodes of acute ischaemia.

[Determination of cardiac troponin I on Stratus analyzer: prospective evaluation in unstable angina]

Cardiac troponin I (troponin lc) has been measured on the Dade Stratus analyzer. Cardiac specificity has been studied in patients presenting a rhabdomyolysis syndrome. The obtained results clearly demonstrated that this parameter may be used as a specific marker of myocardial injury, in contrast to total creatine kinase- or mass CK-MB measurements. In unstable angina, two groups of patients may be defined: one group with elevated troponin lc (> 0.60 microgram/L; 31 patients, group I), one other with normal troponin lc (< 0.35 microgram/L; 49 patients; group II). Quantitative angiographic analysis was performed on 50 patients including 18 patients from group I. Group I showed a more severe culprit lesion than group II. All the results suggested that troponin Ic might be an indicator of severity in unstable angina.

Balloon aortic valvuloplasty in elderly patients at high risk for surgery, or inoperable. Immediate and mid-term results

Although aortic valve replacement is undoubtedly the treatment of choice for aortic valve stenosis, balloon aortic valvuloplasty may represent the only possible treatment for some frail elderly patients who may have additional medical problems. We evaluated immediate and 1-year results of balloon aortic valvuloplasty in 86 patients > or = 80 years with severe aortic stenosis. Mean age was 84 +/- 3 years. Forty-four % were 85 years or older. Mean gradient decreased from 68 to 26 mm Hg and valve area increased from 0.53 to 0.96 cm2 (P<0.05). There were two per-procedural deaths. No local vascular complication was observed. During the follow-up (13 +/- 9 months), 27 patients died, four had repeat balloon aortic valvuloplasty and eight underwent aortic valve replacement. Persistent clinical improvement was observed in 78% of the surviving patients. One-year actuarial survival rate was 73%. Balloon aortic valvuloplasty appears to be a safe and valuable technique in cases where surgery cannot be performed or carries a very high risk.

Angioscopic evaluation of prolonged vs standard balloon inflations during coronary angioplasty. A randomized study

To study the immediate effects of prolonged total balloon inflation during PTCA, 41 patients (44 lesions) with chronic stable angina were randomized for prolonged sequential inflations (three to five inflations of 3 to 5 min each, for a total duration of > or = 12 min, group 1, n = 20 lesions) or 'standard' sequential inflations (three to five inflations of < or = 1 min each, for a total duration of < or = 3 min, group 2, n = 24 lesions). The mean duration of total balloon inflation time was 958 +/- 129 s in group 1 vs 205 +/- 46 s in group 2. Results of angioplasty were assessed on both angiography and percutaneous transluminal coronary angioscopy performed immediately after the procedure. High quality imaging of the coronary lumen and lesion morphology was possible on angioscopy in all patients without any complications. Post-PTCA angiographic percent diameter stenosis was significantly less in group 1 compared to group 2: 26 +/- 10% vs 36 +/- 8% (P < 0.05). On angioscopy, flaps were seen in 16 patients in group 2, but in only six in group 1 (P < 0.02). There was no difference in the incidence of thrombi on angioscopy between the two groups (group 1: nine cases, group 2: 10 cases). Sensitivity of angiographic detection of flaps and thrombi was poor: 10% and 12% respectively. One patient in each group developed a longitudinal dissection, detected on both angiography and angioscopy.

CONCLUSIONS

(1) prolonged sequential balloon inflations lead to less residual luminal stenosis after PTCA, with a decreased incidence of intimal flaps in comparison with standard inflations. (2) Post-PTCA transluminal coronary angioscopy is safe and offers better assessment of luminal effects of PTCA than angiography.

Dobutamine stress echocardiography in orthotopic heart transplant recipients. VACOMED Research Group

OBJECTIVES

This study sought to determine whether dobutamine stress echocardiography could accurately identify coronary artery disease after heart transplantation.

BACKGROUND

After heart transplantation, coronary artery disease is related to either diffuse concentric intimal thickening or focal stenosis and may be underdiagnosed by coronary angiography.

METHODS

We enrolled 41 patients, a mean (+/- SD) of 40 +/- 20 months after heart transplantation, at the time of their routine control coronary angiogram. Three patients were excluded because of poor echogenicity on the angiogram and one because of ventricular premature beats. Standard echocardiographic views were acquired at baseline and at incremental dobutamine infusion levels (from 5 to a maximal dose of 40 micrograms/kg body weight per min at 3-min intervals). Regional wall motion score was calculated from a 16-segment model, and each segment was graded from 1 (normal) to 4 (dyskinesia). Coronary angiography was performed 24 h after dobutamine stress echocardiography, and angiograms were analyzed in blinded manner.

RESULTS

Twenty-three (62%) of 37 patients had normal coronary angiographic findings. Dobutamine stress echocardiography showed abnormalities in only 2 of 23 patients. Fourteen patients (38%) had abnormal angiographic findings, seven of whom had stenoses > 50%. Dobutamine stress echocardiography correctly identified the corresponding hypoperfused segments in these seven patients. More of interest were the other seven patients, of whom three had angiographic nonsignificant stenoses (< 50%), and four had minor diffuse coronary irregularities. Dobutamine stress echocardiography showed hypokinesia in five of these seven patients despite nonsignificant lesions at coronary angiography. The respective overall sensitivity and specificity of dobutamine stress echocardiography were 86% and 91%. At follow-up, 2 of the 37 patients had an acute myocardial infarction. Both had abnormal findings on dobutamine stress echocardiography: One had normal coronary angiographic results, and one had significant coronary lesions.

CONCLUSIONS

Dobutamine stress echocardiography is a useful technique for the diagnosis of coronary artery disease after heart transplantation. These preliminary results indicate that dobutamine stress echocardiography may have a predictive value for further ischemic events in heart transplant recipients.

[Effects of repeated and prolonged inflations on immediate angiographic results and complications of coronary angioplasty. Prospective and randomized study]

The effects of the duration of balloon inflation on the immediate and mid-term results of angioplasty were assessed in a randomized study initiated in June 1992. To date, 239 lesions in 224 consecutive patients were allocated randomly into 2 groups according to the duration of balloon inflation: short duration (123 lesions): 3 or 4 successive inflations, each < or = 1 mn, for a total duration < or = 3 min; long duration (116 lesions): 3 to 5 inflations, each of 4 to 5 minutes each for a total duration > or = 12 min. Patients with acute myocardial infarction, restenosis and lesions of bypass grafts were excluded. Stenosis (% of reduction of the internal diameter) was calculated with a digitalised Philips DCI system. Success was defined by < 50% residual stenosis in the absence of severe complications: death, emergency bypass surgery, infarction and extensive and/or occlusive dissection. The baseline clinical, haemodynamic and angiographic parameters of the two groups were comparable. The residual stenosis after angioplasty in the "short duration" group was 33 +/- 11% and 29 +/- 11% in the "long duration" group (p < 0.05). The primary success rate was 75% in the "short duration" compared to 89% in the "long duration" group (< 0.001). Angiographic dissection after angioplasty was observed in 38 cases in the "short" but only in 17 cases in the "long duration" group (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

[Angioscopic evaluation of the immediate result of coronary angioplasty in relation to balloon inflation time]

The aim of this study was to assess the effects of coronary angioplasty on the intima with respect to the duration of balloon inflation by percutaneous angioplasty. Twenty-seven patients were randomized according to the total duration of balloon inflation: Group I "standard" duration (total duration < or = 3 min, N = 13) and Group II: prolonged duration (total duration > or = 12 min, N = 14); the type and distribution of the lesions were comparable in the two groups. The results of angioplasty were evaluated immediately after dilatation by angiography and angioscopy. Angioscopy was performed without failure or complications with perfect definition of the images in all cases. Angioscopy showed 1) intimal tears, 2) thrombi, 3) longitudinal dissections. A classification in three grades was used taking the apparent gravity of the lesions into consideration. The mean duration of balloon inflation in Group I was 205 +/- 45 s and 958 +/- 129 s in Group II. The residual stenosis was 36 +/- 8% in Group I and 26 +/- 10% in Group II (p < 0.05). Angioscopy showed the frequency of intimal tears to be twice greater in Group I (9 cases) than in Group II (4 cases) (p = 0.05). Intravascular thrombi were observed in 13 cases, 6 in Group I and 7 in Group II. One case of longitudinal dissection was observed in each group: only one of these two cases was detected at angiography. The authors conclude that repeated and prolonged balloon inflations improve the immediate results of angioplasty with less residual stenosis at angiography and a lower incidence of intimal tears at angioscopy.

[Ablation by radiofrequency in the treatment of atrial arrhythmia]

Atrial arrhythmias resistant to medical therapy are still a common indication for ablation of the normal atrioventricular conduction pathway (Tawara node and His Bundle). However, the development of catheter techniques of intra-atrial ablation to destroy arrhythmogenic myocardial zones enables radical cure of the arrhythmias with the respect of the nodo-hisian pathway. With respect to common flutter, a number of series, including our own, show a 50 to 75% long-term success rate. We believe that a very high success rate in the ablation of flutter will probably be achieved in a reproducible manner but this will require a more accurate understanding of the tachycardia circuit and technological developments allowing controlled radio-frequency destruction of bigger atrial myocardial zone. Experience of radio-frequency ablation atrial of atrial extrasystoles is more limited than that of flutter and there are fewer published series. Globally, catheter ablation of atrial tachycardia remains a more difficult and a less well codified procedure than that of accessory pathways or of intra-nodal reentry. Radio-frequency ablation in this indication is not without danger in view of the thinness of the atrial wall. We believe that radio-frequency catheter ablation for atrial arrhythmias should, for the moment, be reserved for centres specialised in the techniques of electro-physiological investigation and ablation.

[Current status of aortic valvuloplasty in patients aged 80 and over. Apropos of a recent series of 70 patients (1989-90)]

In contrast with aortic valve replacement, the treatment of choice for severe aortic stenosis because of the better long-term results, percutaneous aortic valvuloplasty, has only limited indications, mainly because of the high rate of restenosis. However, in very elderly patients, the surgical risk is high, sometimes prohibitive. For this reason, the authors report their latest results with this technique in a series of octogenarians. Between January 1989 and December 1990, 70 aortic valvuloplasties were performed in octogenarians (average age 85 +/- 3 years). The indications were advanced age > or = 85 years (46%), poor left ventricular ejection fraction < 40% (20%), secere associated coronary artery disease (3%), associated extracardiac pathology (11%), poor general condition (11%) or refusal of surgery (4%). The great majority of these patients (83%) were very symptomatic: 70.5% had Grade III-IV dyspnoea, 20% had Grade III-IV angina and 20% had syncopal attacks. Valvuloplasty reduced the mean transvalvular pressure gradients from 61 +/- 23 to 30 +/- 11 mmHg (p < 0.01) and increased aortic valve surface area from 0.53 +/- 0.19 to 0.94 +/- 0.12 cm2 (p < 0.001). There were two deaths (2.9%) in the catheterization laboratory and 4 (5.7%) complications during the hospital period (myocardial infarction: 1, cerebrovascular accident: 1, severe aortic regurgitation: 1 and complete atrio-ventricular block: 1). There were no serious vascular complications. The average duration of the hospital period was 6 +/- 5 days. Clinical follow-up of 17 +/- 7 months was obtained in 97% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[Simplified continuity equation: absence of predictive value in assessing severity of mitral valve stenosis]

The object of this study was to assess the accuracy of the simplified continuity equation (SCE) defined as the ratio of velocity time integrals (VTI) of the aortic or pulmonary to mitral orifice in the evaluation of severe mitral stenosis. The results of the continuity equation and VTI ratios were compared with the Gorlin catheter valve area in 70 patients with pure mitral stenosis in sinus rhythm. The continuity equation (CE) and SCE were significantly correlated (p < 0.01) with the Gorlin surface area with a better coefficient with the CE (r = 0.86) than with the VTI ratio (r = 0.74). The patient population was divided into two groups depending on the severity of mitral stenosis; Group I had catheter valve areas of less than 1.5 cm2: 38 patients had mean value of the CE of 1.11 +/- 0.22 cm2 and of the SCE of 0.32 +/- 0.09. In Group II (mitral valve area > or = 1.5 cm2), 32 patients had a mean CE value of 1.92 +/- 0.29 cm2 and a SCE value of 0.56 +/- 0.14. Only two patients in Group I had SCE values greater than 0.5. Conversely, no patients in Group II had a SCE value of less than 0.3. For a range of SCE values of 0.3 to 0.5, there was an important overlap between the two groups (19 patients of Group I and 9 patients of Group II).(ABSTRACT TRUNCATED AT 250 WORDS)

Results of balloon aortic valvuloplasty in patients with aortic stenosis associated with significant aortic regurgitation

The influence of balloon aortic valvuloplasty (BAV) on aortic regurgitation (AR) in patients with severe aortic stenosis associated with greater than or equal to grade II AR was studied by supraaortic angiogram before and after BAV. The results of 50 patients aged 72 +/- 12 years with significant AR before BAV (group A) were compared to 297 patients (mean age 76 +/- 10 years) with no or mild AR (group B). In group A, the patients had a higher left ventricular end diastolic volume (96 +/- 19 mL/m 2 vs 81 +/- 32 mL/m 2, P less than 0.01) and left ventricular end diastolic pressure (23 +/- 9 mmHg vs 19 +/- 9 mmHg, P less than 0.01). The aortic valve area was similar in both groups. Following BAV, the improvement in aortic valve area and hemodynamics were similar in both groups. In group A, AR remained unchanged in 31 patients (62%), increased by 1 grade in 13 patients (26%), and decreased by 1 grade in 6 patients (12%). In group B, AR increased by greater than 1 grade in 34 patients (11%) and greater than 2 grades in 4 patients (1.3%) post-BAV. Two patients in group B underwent emergency aortic valve replacement following BAV because of severe acute AR. In conclusion, when it is indicated, BAV can be performed with similar risk in patients with significant AR.

Progressive decrease in myocardial ischemia assessed by intracoronary electrocardiogram during successive and prolonged coronary occlusions in angioplasty

Progressive decrease in chest pain and surface ECG changes are commonly observed during successive balloon inflations in coronary angioplasty, which suggests a decrease in myocardial ischemic response. To assess this hypothesis, we continuously recorded intracoronary ECGs during four balloon inflations; each of the inflations was maintained to a minimum of 120 seconds in 19 patients who had significant stenosis in the left anterior descending artery and normal left ventricular function. Three successive QRS-T complexes were analyzed on surface and intracoronary ECGs for measurements of ST-segment elevation 60 milliseconds after the J point. Surface ECG changes were compared with intracoronary ECG changes. On intracoronary ECG, ST area (in square millimeters) and T wave amplitude (in millimeters) were also computed. Chest pain was noted as present or absent during each successive balloon inflation. Ability of intracoronary ECG to detect myocardial ischemia, which was defined as ST-segment elevation greater than 1 mm during balloon inflations 1 to 4, was 89%, 89%, 84%, and 74%, respectively and was higher than that of surface ECG, which was 68%, 63%, 68%, and 58%, respectively. On intracoronary ECG, when compared with the first balloon inflation, a significantly smaller increase in ST-segment elevation was noted during each subsequent balloon inflation, whereas a significantly smaller increase in ST area and T wave amplitude was noted only during balloon inflation 4. The number of patients who experienced chest pain decreased from 15 to 13, 10 and 6 from the first to the fourth balloon inflation. This report demonstrates a progressive decrease in myocardial ischemic response during successive and prolonged balloon occlusions.(ABSTRACT TRUNCATED AT 250 WORDS)

Improved myocardial ischemic response and enhanced collateral circulation with long repetitive coronary occlusion during angioplasty: a prospective study

OBJECTIVES

The goal of the study was to evaluate the progressive increase in ischemic threshold with multiple sequential transient coronary occlusions and to assess the role of the collateral circulation in adaptation to ischemia.

BACKGROUND

It has been observed that the duration of balloon inflations during coronary angioplasty can be gradually prolonged during subsequent dilations with a reduction in patient symptoms and diminished ischemic electrocardiographic (ECG) changes. Although the mechanism has not been fully explained, recruitment of coronary collateral circulation induced by repeated coronary occlusion has been reported. The stimuli for recruitment and the natural history of coronary collateral circulation are not understood.

METHODS

Seventeen patients with isolated stenosis of the left anterior descending coronary artery and a normal left ventricle were enrolled. Angioplasty consisted of five successive prolonged inflations. Sequential changes in clinical, intracoronary ECG and left ventricular indexes of myocardial ischemia were examined. Coronary collateral channels were evaluated during balloon inflations by ipsilateral and contralateral injections of contrast medium and hemodynamically by occlusion pressure.

RESULTS

An improved tolerance to myocardial ischemia with repetitive coronary occlusions was demonstrated by a significant reduction of angina, ST segment deviation, left ventricular filling pressure and less impairment of ejection fraction. Left ventricular wall motion abnormalities remained unchanged. Collateral angiographic grade did not change in 7 patients and increased in 10.

CONCLUSIONS

This study confirms a progressive adaptation of myocardial ischemia to repetitive coronary occlusions and supports the concept that sequential episodes of myocardial ischemia are a stimulating factor for the recruitment of collateral channels in humans. These results also suggest that enhancement of recruitable collateral circulation might be an underlying mechanism of myocardial ischemic preconditioning.

Repeat balloon aortic valvuloplasty

This paper attempts to determine limitations and indications of performing a second balloon aortic valvuloplasty procedure (BAV2) because of restenosis, which is the major limitation of this technique. From September 1985 to December 1989, 357 patients underwent a primary BAV (BAV1) and 67 patients had a BAV2. Forty-two patients (group A) had repeat catheterization because they were markedly symptomatic 11 +/- 7 months after BAV1. Twenty-five patients (group B) came from a group of 73 patients who had been systematically scheduled for repeat catheterization in order to evaluate the hemodynamic restenosis rate 8 +/- 3 months after BAV. At time of BAV2 most of the patients of group A were severely disabled. Comparison of pre-BAV2 gradient and aortic valve area with pre-BAV1 measurements showed in a slightly less severe degree of aortic stenosis in group A and in group B with any difference in cardiac index and ejection fraction. Immediately following BAV2, the gradient decreased from 72 +/- 22 to 33 +/- 15 mm Hg (P less than 0.001) and aortic valve area increased from 0.56 +/- 0.18 to 0.85 +/- 0.28 cm2 (p less than 0.001) in group A. In group B, gradient decreased from 68 +/- 15 to 33 +/- 15 mm Hg (p less than 0.001) and aortic valve area increased from 0.70 +/- 0.16 to 0.90 +/- 0.25 cm2 (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of restenosis after balloon dilatation in adult aortic stenosis by repeat catheterization

To evaluate the restenosis rate after successful balloon aortic valvuloplasty, clinical evaluation and repeat catheterization were performed in 96 patients who had undergone balloon dilatation 7 +/- 5 months earlier. Restenosis, defined as a loss of greater than 50% of the benefit in aortic valve area obtained after balloon valvuloplasty, was observed in 48% of the patients. Actuarial analysis showed that the restenosis rate was time dependent and was 80% at 15 months. However, functional improvement was observed in most of the patients with or without restenosis. The restenosis rate was not correlated with the degree of enlargement of the aortic orifice produced by the valvuloplasty procedure. Because of the high incidence of restenosis, balloon aortic valvuloplasty should be limited to patients who have a contraindication to surgery or are at high risk for surgery, or as a bridge to surgery.

[Percutaneous aortic valvuloplasty as a last resort in patients with critical aortic valve stenosis]

Emergency aortic valvuloplasty was performed as a last resort in 34 patients with an average age of 76 years with critical aortic stenosis in the terminal stages with congestive cardiac failure or cardiogenic shock. Emergency aortic valve replacement was considered to be too risky in these cases. The valve was dilated in all patients, resulting in a fall in mean peak-to-peak pressure gradients from 59 mmHg to 21 mmHg and an increase in valve surface area from 0.42 cm2 to 0.85 cm2. Significant improvement in myocardial function was observed immediately after the procedure with an increase of the cardiac index from 1.77 l/min/m2 to 2.07 l/min/m2 and of the ejection fraction from 28% to 35%. Complications were rare. There were no deaths or cerebrovascular accidents during the valvuloplasty procedure. Two patients died in hospital (6%) after the dilatation and two other patients who had persistent pulmonary oedema, underwent surgery; one died and the other had a good surgical result. A clear cut clinical improvement was obtained in the other 30 patients. The patients were followed up for an average of 15 +/- 7 months during which 15 died (50%), 6 +/- 5 months after dilatation. The other 15 survivors have a significant and unhoped for functional improvement. Three young patients later underwent surgical valve replacement in good clinical conditions with the same operative risk as that of standard candidates for aortic valve surgery. One other patient was operated on successfully during another relapse of cardiac failure. These results show that aortic valvuloplasty may be undertaken with a low risk even in the most critical clinical situations and that the procedure rapidly relieves the invalidating symptoms. It may be used as a bridge to surgery in patients with an unacceptable operative risk. The indications should be very flexible in young patients in terminal cardiac failure with cardiogenic shock or refractory pulmonary oedema.

Aortic stenosis in elderly patients aged 80 or older. Treatment by percutaneous balloon valvuloplasty in a series of 92 cases

Very elderly patients with severe aortic stenosis will probably benefit from percutaneous balloon valvuloplasty. Ninety-two patients, aged 80 or older (mean age, 84 +/- 3.7 years) and all severely incapacitated (18 with an associated pathologic condition or in critical condition with terminal heart failure), underwent a valvuloplasty procedure. Femoral access was used in all cases except seven (8%), in whom the femoral route had to be abandoned and the brachial approach was used due to severe arterial tortuosity. Peak-to-peak ventriculoaortic gradient decreased from 71 +/- 27 to 27 +/- 15 mm Hg, and the aortic valve area increased from 0.48 +/- 0.16 to 0.91 +/- 0.35 cm2 (p less than 0.01). Thirty-two percent had a postprocedure aortic valve area more than or equal to 1 cm2. The final valve area was less than or equal to 0.7 cm2 in 30% of the patients. There were three deaths (ages, 82, 92, and 98 years) in the procedure room. One stroke occurred 1 day after the procedure. Hematoma or thrombosis at the femoral puncture site was observed in 14 cases (15%), requiring surgical repair in only five cases. Three patients died in the hospital; the total in-hospital mortality was 6.5%. Among the 62 patients about whom information could be obtained at a mean follow-up interval of 13 +/- 5 months, there were 18 late deaths (mean age, 85 +/- 11 years). The majority of the surviving 44 patients experienced marked symptomatic improvement. The results indicate that balloon valvuloplasty can be offered to very elderly patients with severe aortic stenosis and can produce improvement in hemodynamic and clinical status.

Percutaneous balloon valvuloplasty in patients with severe aortic stenosis and low ejection fraction. Immediate results and 1-year follow-up

The efficacy, morbidity, and 1-year follow-up of balloon aortic valvuloplasty in patients with low ejection fraction (less than 40%) were studied on a consecutive series of 55 patients (mean age, 77 years) treated from September 1985 to February 1987. Because of their age (20 patients greater than 80 years old), poor left ventricular function, and associated diseases, 45 patients were definitely not surgical candidates. Balloon dilatation with 15-23-mm diameter balloon catheters decreased the transvalvular gradient from 66 +/- 24 to 28 +/- 14 mm Hg (p less than 0.001) and increased the valve area from 0.47 +/- 0.15 to 0.83 +/- 0.27 cm2 (p less than 0.001). Immediately after dilatation, ejection fraction mildly increased from 29 +/- 7% to 34 +/- 9% (p less than 0.001) in 38 patients who had undergone a second left ventricular angiogram after dilatation. No significant change in the degree of aortic regurgitation was found after the procedure. Three patients died in hospital (femoral arterial complications in two, septicemia in one). Immediate clinical improvement was noted in 80% of the patients. During the follow-up (mean, 11 months), 22 patients died (heart failure in 15 patients, sudden death in five patients, myocardial infarction in one patient, cancer in one patient). Thirty patients survived, 21 with persistent clinical improvement. Repeat cardiac catheterization was performed at 6 months in 20 patients, of whom eight had recurrence of symptoms. Nine patients had restenosis: their hemodynamic indexes had returned to prevalvuloplasty values.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects and chronology of coronary restenosis after percutaneous transluminal coronary angioplasty. Quantitative angiographic analysis at 1, 2, 3, 4 and 5 months]

Coronary restenosis occurs fairly early after transluminal coronary angioplasty, as suggested by anatomico-clinical, isotopic and angiographic studies. Its incidence, as reported in the literature, varies according to the clinical selection of patients, to the number of patients with follow-up angiography and the timing of this procedure, and to the criteria used to define restenosis. In this prospective study we endeavoured to determine the exact date at which restenosis takes place, as well as its true incidence, by means of 6 different angiographic criteria. The population studied was divided into five groups and each group underwent coronary arteriography at a different date: during the 1st, 2nd, 3rd, 4th and 5th post-angioplasty months respectively. In 424 of the 500 patients thus examined (84.8 p. 100), coronary angiography involved automatic detection of contours and made quantitative analysis possible. Coronary restenosis was found to occur early, with a peak of incidence in the 3rd month. Its incidence varied considerably depending on the criterion used. A critical analysis of the data has prompted us to use a criterion based on absolute values determined by quantitative angiographic analysis.

[Treatment of acquired aortic stenosis in adults by percutaneous valvuloplasty with balloon catheterization. Experience of 245 cases]

In our department, percutaneous balloon valvuloplasty has become the routine treatment of aortic valve stenosis in adults. We report here the results obtained in 245 consecutive patients. The patients' age varied between 30 and 98 years (mean 74 +/- 11 years), 77 of them (31 p. 100) being 80 years' old or older. The initial peak to peak ventriculo-aortic gradient was 72 +/- 25 mmHg and the aortic valve area was 0.53 +/- 0.17 cm2. After dilatation the gradient was reduced to 29 +/- 14 mmHg (p less than 0.001) and the aortic valve area was increased to 0.95 +/- 0.33 cm2 (p less than 0.0001). The aortic valve area was increased by 100 p. 100 or more in 83 patients (34 p. 100) and by less than 25 p. 100 in only 17 patients (7 p. 100). The ventricular ejection fraction rose slightly but significantly from 48 +/- 18 p. 100 to 51 +/- 17 p. 100 (p less than 0.01). One patient developed massive regurgitation and had to undergo semi-emergency surgery. The experience acquired and the use of better catheters enabled us to improve these results by almost doubling the number of patients whose aortic valve area became 1 cm2 or more and by reducing by half those whose aortic valve area remained 0.7 cm2 or less. Three patients aged 82, 91 and 98 respectively died, and there was one cerebral vascular accident in the catheterization room. Nine patients (4 p. 100) died in hospital during the following days.(ABSTRACT TRUNCATED AT 250 WORDS)

[Assessment of immediate geometric changes in coronary stenosis after implantation of stents by quantitative angiographic analysis]

In order to assess the immediate geometric changes in coronary stenosis that occur after implantation of intra-coronary stents, a quantitative angiographic analysis (automatic delineation of contours) was performed in 18 patients. Following angioplasty, the implantation of a stent significantly increases the diameter and area of the stenotic segment in absolute values. This improvement is attended by a significant decrease in resistance and in the theoretical trans-stenotic pressure gradient. Beside its role as mechanical support of the dilated arterial wall, the stent possesses an intrinsic force of dilatation confirmed by the results of quantitative angiographic analysis.

Insights on the mechanism of balloon valvuloplasty in aortic stenosis

An analysis of the mechanisms of action of balloon valvuloplasty in adult aortic stenosis (AS), based on postmortem studies on fresh specimens and on clinical experience with 300 consecutive cases, is reported. When maximally inflated, a 20-mm diameter balloon (occupying a 3.14 cm2 cross-sectional area) significantly enlarges the stenosed valve orifice by 3 mechanisms: stretching of valve tissue, rupturing of commissural fusion and breaking of calcific deposits. These last 2 mechanisms are the most effective, in both tricuspid and bicuspid forms of AS, to render the cusps more flexible and able to open during systole and to close at the time of ventricular diastole. The marked increase in valve area obtained by the dilatation procedure was clearly demonstrated on fresh postmortem specimens and also on postmortem examination of cases that had had balloon valvuloplasty during life. Stretching alone may give only a temporary increase in valve area with an elastic return of the leaflets to their initial stenosing position and may explain, at least in part, the occurrence of restenosis. Inflation of the balloon is well tolerated with no deleterious decrease in blood pressure in two-thirds of the cases because the balloon opens the commissures, allowing blood ejection through these openings. It does not produce calcific emboli, probably because calcium deposits remain imbedded in the leaflets, covered by the endothelium. Finally, it very infrequently produces acute severe aortic regurgitation. Careful choice of balloon size is necessary to obtain on effective opening; most often a 20-mm diameter balloon but sometimes a balloon up to 23 mm is used.(ABSTRACT TRUNCATED AT 250 WORDS)

Results of percutaneous transluminal valvuloplasty in 218 adults with valvular aortic stenosis

The results of balloon aortic valvuloplasty (BAV) in 218 adult patients with valvular aortic stenosis (AS) are reported. In most cases, 3 transcutaneously introduced balloons of successively increasing size were used. Tolerance was excellent in 64%, whereas a decrease in blood pressure below 60 mm Hg during inflation was observed in 36%. The left ventricular-aortic peak to peak gradient decreased from 72 +/- 25 to 29 +/- 14 mm Hg (p less than 0.001) and the aortic valve area increased from 0.52 +/- 0.18 to 0.93 +/- 0.33 cm2 (p less than 0.001). The final aortic valve area was greater than or equal to 1 cm2 in 69 patients (32%). In only 6 cases (3%) the aortic valve area did not change or increased by less than 10%. A clear improvement in the results was observed with gained experience and better catheters. There was 1 death and 1 stroke in the procedure room, and 3 strokes after BAV. Nine patients died shortly after the procedure. There were local complications (hematoma or thrombosis) at the femoral puncture site in 28 (13%) patients. Clinical follow-up was obtained for 144 patients (mean 8 months). There were 24 deaths. In the 120 remaining cases, symptomatic improvement was good in 84%, with decrease or disappearance of dyspnea, angina or both. This study demonstrates that BAV is feasible in adult AS at a low risk and is able to produce marked clinical improvement in most cases.