[Coronary surgery of the beating heart. First year of experience in a series of 317 non-selected coronary patients]

From May 1999 to May 2000, 317 unselected patients, representing 92.7% of all coronary artery surgery procedures, underwent open heart surgery of the beating heart by median sternotomy with the aid of a cardiac stabilising device. The main preoperative characteristics were: mean age = 66.1 years; men = 78.9%; left main stem disease = 31.8%; mean left ventricular ejection fraction = 54.1%; mean Parsonnet index = 16.9. These 317 patients were compared with a group of 303 patients who underwent coronary bypass surgery the year before by the same surgical team with cardiopulmonary bypass (CPB) and cardiac standstill. Seven hundred and eighty-six distal anastomoses were carried out in the beating heart group (2.48 grafts per patient) compared with 2.91 in the CPB group: p < 0.001). There were 10.1% single bypass, 37.5% double bypass, 47.3% triple bypass and 5% quadruple bypass procedures. A cardiopulmonary bypass was required in 13 patients (4.1%). The mortality at 30 days was 3.1% versus 4.6% in the CPB group (p = NS). The need for blood transfusion was reduced by nearly 40% in the beating heart group (23.7% versus 39.9%, p < 0.001). The incidence of cerebrovascular complications was reduced from 3% in the CPB group to 0.6% in the beating heart group (p = 0.06). The peak postoperative troponine I levels were much lower in the beating heart group (2.5 versus 6.4 ng/ml, p < 0.001). The authors conclude that surgery on the beating heart is feasible in most patients. Compared with conventional surgery under CPB, there seems to be less requirement for blood transfusion and a tendency to reduce the cerebral risk. Nevertheless, a large prospective randomised trial is required to validate the potential advantages and limitations of this technique with respect to conventional surgery and to determine the optimal indications of surgery on the beating heart.

Thallium gated SPECT: relation between immediate post-stress evolution of ejection fraction and severity of perfusion pattern

BACKGROUND AND AIMS

A significant decrease of left ventricular ejection fraction (LVEF) at stress has been reported with 99Tc(m) gated single-photon emission computed tomography (gSPECT) in severe myocardial stunning up to 1 h after exercise. This study was designed to show whether 201Tl gSPECT can measure LVEF evolution from rest to stress in routine examination and give additional information to perfusion interpretation since acquisition starts immediately after stress test.

METHODS

Post-exercise and rest 201Tl gSPECT were performed in 187 patients with suspected coronary artery disease. Myocardial perfusion was quantified by 20-segment analysis. Patients were divided into four groups according to their summed perfusion score, reversibility rate and electrocardiographic findings, i.e. in order of severity: I = normal perfusion, II = fixed defect owing to a myocardial infarction, III = full reversible ischaemia, and IV = partial reversible ischaemia. LVEF was calculated by Germano's automatic algorithm.

RESULTS

Normal subjects (n = 29) and infarcted patients (n = 34) showed a significant LVEF increase between rest and stress, +7 +/- 9% and +5 +/- 7% respectively. In full reversible ischaemic patients (n = 46), stress LVEF showed no increase (+1 +/- 8%) and this group was statistically different from both group I and group II. Furthermore, when ischaemia was partially reversible (n = 31), LVEF decreased significantly (-3 +/- 8%), particularly when exercise tests were abnormal (-4 +/- 8%). Group IV was statistically different from groups I and II.

CONCLUSIONS

Good agreement exists between the severity of ischaemic perfusion pattern and LVEF degradation at stress, which is consistent with previously published data using 99Tc(m) gSPECT. Additionally, the use of 201Tl for immediate post-exercise imaging allows the observation of a physiological LVEF increase in normal and infarcted patients.

[Comparison of segmental wall motion in electrocardiogram-gated myocardial scintigraphy and transthoracic echocardiography]

ECG-gated myocardial scintigraphy (Gspect) is a recent method of assessing myocardial perfusion, left ventricular ejection fraction and regional wall motion in a single investigation. It reduces the time required for the evaluation of coronary patients by radionucleide cardiology. Many reports have validated the measurement of the left ventricular ejection fraction compared with other methods. However, there are fewer series reporting the results of regional wall motion. The authors compared segmental wall motion by Gspect after injecting Thallium or Mibi and by transthoracic echocardiography in 47 patients or 423 myocardial segments. The concordance of score (normal, hypokinetic, akinetic, dyskinetic) was 75% (Kappa = 0.538). If analysis was limited to a normal-abnormal differentiation (binary analysis) it increased to 83%. When perfusion was taken into consideration, it was 81% (normal perfusion), 63% (mild hypoperfusion) and 70% (moderate and severe hypoperfusion). This concordance improved in binary analysis respectively to 85, 74 and 86% respectively. When the typs of segment was taken into consideration, concordance varied from 57 to 100%. The concordances were 74% for Thallium and 78% for Mibi scintigraphy, improving to 82% and 85% respectively in binary analysis. Thus, analysis of LV regional wall motion by Gspect is comparable to transthoracic echocardiography. This result, completed by measurement of LV ejection fraction and of myocardial perfusion, provides a method of evaluation of coronary patients in a single investigation.

[Postoperative infections after heart surgery under extracorporeal circulation]

Postoperative infection is still an important cause of mortality and morbidity after cardiac surgery. The aim of this study was to assess its incidence and causes in order to optimise treatment. Between January 1996 and December 1997, 1,000 consecutive patients (253 women and 747 men) were operated for cardiac aortic pathology under cardiopulmonary bypass. The mean age was 66 +/- 11 years. The initial pathology was coronary artery disease (N = 663), valvular heart disease (N = 193), an association of the two (N = 94), thoracic aortic pathology (N = 38) or other pathologies (N = 12). The global postoperative infection rate was 4.9% (N = 49). The incidence of sternal and/or mediastinal infections was 0.7%, of bronchopneumonia 0.9%, urinary infection 2.1%, and septicaemia 1.7%. Nine patients died of the consequences of an infection. The hospital stay was significantly longer in infected patients, irrespective of the site of infection. Statistical analysis of the whole population did not show any predictive factor related to the preoperative clinical status of the patients. The only predictive factor demonstrated was the day on which surgery was performed: the infection rate in patients operated during the first 4 days of the week was 2.2% compared with 7.3% for the patients operated during the last 3 days (p = 0.004, odds ratio (OR) = 3.57). In those patients who had an urinary infection, the two identified risk factors were the female gender (p = 0.006, OR = 3.34) and an operation performed at the end of the week (p = 0.017, OR = 3.77). In patients with sternal and medistinal infections, the only identified predictive factor was combined coronary artery and valvular surgery (p = 0.009, OR = 7.43). With respect to pulmonary infections, the only predictive factor was recent preoperative myocardial infarction (< 1 month) (p = 0.004, OR = 7.5). Finally, no predictive risk factors were identified in those patients who developed septicaemia. In conclusion, this study showed that postoperative infection remains a serious complication of cardiac surgery. The prevention of these complications should be a priority for quality health care.

Identification of a genetic risk factor for idiopathic dilated cardiomyopathy. Involvement of a polymorphism in the endothelin receptor type A gene. CARDIGENE group

BACKGROUND

Idiopathic dilated cardiomyopathy is a frequent cause of heart failure, a major concern of public health. Although idiopathic dilated cardiomyopathy may be familial, most cases are sporadic and the disease is considered to be multifactorial, for which genetic factors may account for a significant part.

METHODS AND RESULTS

We hypothesized that genetic abnormalities of the endothelin pathway may be involved in idiopathic dilated cardiomyopathy pathophysiology and therefore examined the possible association between idiopathic dilated cardiomyopathy and polymorphisms in genes encoding endothelin 1, endothelin type A and type B receptors, in a case-control study (433 patients and 400 age- and sex-matched control subjects). Analysis of the Exon 8 C/T polymorphism in the endothelin receptor type A gene indicated that individuals who are homozygote for the T allele were at significantly increased risk for the disease (odds ratio: 1.9; 95% confidence interval: 1.2 to 3. 01;P<0.006). Analysis of the other polymorphisms indicated that no significant difference was observed in genotype or allele frequencies between cases and controls.

CONCLUSIONS

The variant in the Exon 8 of the endothelin receptor type A gene appears as a genetic risk factor for idiopathic forms of heart failure. These results provide a new approach to the pathophysiology of idiopathic dilated cardiomyopathy.

Prognostic value of MIBG imaging in idiopathic dilated cardiomyopathy

Alterations of cardiac sympathetic innervation are likely to contribute to fatal outcomes in patients with heart failure. These alterations can be evaluated noninvasively by 123I-metaiodoben-zylguanidine (MIBG) imaging.

METHODS

The hypothesis that impaired cardiac sympathetic innervation, as assessed using MIBG imaging, is related to adverse outcomes was tested in 112 patients with heart failure resulting from idiopathic cardiomyopathy. Main inclusion criteria were New York Heart Association classes II-IV and radionuclide left ventricular ejection fraction (LVEF) < 40%. Patients were assessed for cardiac MIBG uptake, circulating norepinephrine concentration, LVEF, peak Vo2, x-ray cardiothoracic ratio, M-mode echographic end-diastolic diameter and right-sided heart catheterization parameters.

RESULTS

During a mean follow-up of 27 +/- 20 mo, 19 patients had transplants, 25 died of cardiac death (8 sudden deaths), 2 died of noncardiac death and 66 survived without transplantation. The only independent predictors for mortality were low MIBG uptake (P < 0.001) and LVEF (P = 0.02) when using multivariate discriminant analysis. Moreover, MIBG uptake (P < 0.001) and circulating norepinephrine concentration (P = 0.001) were the only independent predictors for life duration when using multivariate life table analysis.

CONCLUSION

Impaired cardiac adrenergic innervation as assessed by MIBG imaging is strongly related to mortality. MIBG imaging may help risk stratify patients with heart failure resulting from idiopathic dilated cardiomyopathy.

Sympathetic nerve alterations assessed with 123I-MIBG in the failing human heart

Norepinephrine (NE) reuptake function is impaired in heart failure and this may participate in myocyte hyperstimulation by the neurotransmitter. This alteration can be assessed by 123I-metaiodobenzylguanidine (MIBG) scintigraphy.

METHODS

To determine whether the impairment of neuronal NE reuptake was reversible after metoprolol therapy, we studied 18 patients (43+/-7 y) with idiopathic dilated cardiomyopathy who were stabilized at least for 3 mo with captopril and diuretics. Patients underwent, before and after 6 mo of therapy with metoprolol, measurements of radionuclide left ventricular ejection fraction (LVEF), maximal oxygen consumption and plasma NE concentration. The cardiac adrenergic innervation function was scintigraphically assessed with MIBG uptake and release measurements on the planar images obtained 20 min and 4 h after tracer injection. To evaluate whether metoprolol had a direct interaction with cardiac MIBG uptake and release, six normal subjects were studied before and after a 1-mo metoprolol intake.

RESULTS

In controls, neither cardiac MIBG uptake and release nor circulating NE concentration changed after the 1-mo metoprolol intake. Conversely, after a 6-mo therapy with metoprolol, patients showed increased cardiac MIBG uptake (129%+/-10% versus 138%+/-17%; P = 0.009), unchanged cardiac MIBG release and decreased plasma NE concentration (0.930+/-412 versus 0.721+/-0.370 ng/mL; P = 0.02). In parallel, patients showed improved New York Heart Association class (2.44+/-0.51 versus 2.05+/-0.23; P = 0.004) and increased LVEF (20%+/-8% versus 27%+/-8%; P = 0.0005), whereas maximal oxygen uptake remained unchanged.

CONCLUSION

Thus, a parallel improvement of myocardial NE reuptake and of hemodynamics was observed after a 6-mo metoprolol therapy, suggesting that such agents may be beneficial in heart failure by directly protecting the myocardium against excessive NE stimulation.

[Importance of dual isotope myocardial tomoscintigraphy in the detection of coronary disease in the graft among 96 heart transplant recipients]

With a survival rate of 70% at 3 years, cardiac transplantation is the best treatment for end-stage heart disease. However, progressive development of graft atherosclerosis is frequent. Diagnosis of transplant coronary disease remains difficult and non-invasive tests have proved relatively insensitive. Therefore, coronary angiography performed annually is still the gold-standard test for the detection of heart transplant vasculopathy. We analyzed the records of 96 patients (82 men and 14 women) who were transplanted from 1986 to 1996. Mean age was 53 +/- 2.7 and time elapsed from transplantation was mean 5.3 +/- 10 years. All patients had rest myocardial TI 201 perfusion SPECT, followed by MIBI gated SPECT after exercise. MIBI gated SPECT allows simultaneous evaluation of perfusion, regional LV function and global ejection fraction. Angiocoronarography, performed in all patients during the six months following radionuclide investigation, showed the presence of coronary heart vasculopathy in nine (9.3%). Seven of these patients had abnormal dual isotope imaging and 2 of them had normal perfusion but altered LV regional function. Sensitivity of dual isotope scintigraphy was 77% and specificity was 97.7%. Dual isotope scintigraphy is helpful to detect coronary vasculopathy in heart transplant recipients and may reduce indications of angiocoronarography.

[Comparative study of the global left ventricular ejection fraction obtained by ECG gated perfusion MIBI and thallium scintigraphy]

The isotopic LVEF was measured by a planar method with injection of a product visualising the ventricular cavity. Perfusion was assessed by Thallium and sesta MIBI. The investigation of ischaemia and assessment of wall motion in the coronary patient, therefore, requires two isotopic methods. The Cedars Sinai group have developed a programme allowing acquisition of a perfusion tomoscintigraphy in the cardiac cycle after injection of MIBI. This programme automatically detects the endocardial borders and calculates the LVEF. This provides a study of function and perfusion in a single investigation. However, MIBI is not considered by all as a good marker of viability, contrary to Thallium. And the acquisition of Thallium tomography with ECG gating may pose problems because of the low counting statistic. Several authors have therefore studied the possibility of using it for assessing left ventricular function. The authors have then compared LVEF with MIBI and with Thallium in 72 patients. The Thallium LVEF was 33.62% +/- 15.79%; that of MIBI was 32.51% +/- 14.73%. ThalEF = MIBI EF x 1.02 + 0.34 (r = 0.955). The mean of the standard deviation was 1.09. In conclusion, the EF measured by Thallium tomography with ECG gating was closely correlated to that obtained with MIBI. These results suggest that myocardial viability, ischaemia and function may be studied in routine daily practice with a single injection, so improving patient comfort and reducing the costs of the procedures.

[Mitral valvuloplasty for asymptomatic or pauci-symptomatic mitral insufficiency]

The aim of this study was to assess the results of mitral valvuloplasty for chronic asymptomatic or paucisymptomatic mitral regurgitation. Of 584 patients operated for chronic mitral regurgitation between January 1989 and December 1994, 175 were in NYHA Classes I and II and made up the study population. All had chronic grade 3 or 4/4 mitral regurgitation suitable for mitral valvuloplasty. The average follow-up was 34.3 months. Mitral valvuloplasty was performed in 174 patients, the other patient requiring mitral valve replacement. Three patients died (1.7%) and the actuarial 5 year survival was 98.2 +/- 1.0%. The probability of absence of reoperation and absence of thrombo-embolic complications at 5 years were 97 +/- 0.8% and 96.3 +/- 1.7% respectively. The residual regurgitation at Doppler echocardiography was minimal or absent in 94% of patients at the last follow-up control. The mean end-systolic and end-diastolic left ventricular dimensions decreased from 40.0 +/- 6.8 mm and 64.8 +/- 7.0 mm before surgery to 34.6 +/- 6.7 mm (p < 0.001) and 52.7 +/- 7.4 mm (p < 0.001) at the last control. The authors conclude that conservative mitral valve surgery for NYHA Classes I and II patients with chronic mitral regurgitation is feasible with a low risk and is associated with a significant reduction in ventricular volumes and stability of valvular continence at medium-term. When performed by teams trained in techniques of mitral valvuloplasty, these results suggest that surgery should be performed early.

Clinical evaluation of the Physio annuloplasty ring

STUDY OBJECTIVES

Prospective evaluation of a selectively flexible annuloplasty ring was undertaken to assess its safety and efficacy.

PATIENTS

Between December 1992 and November 1996, 190 patients with mitral regurgitation underwent mitral valve repair using an annuloplasty ring (Carpentier-Edwards Physio; Baxter-Edwards CVS Laboratories; Irvine, Calif). Ninety-four were in New York Heart Association class I or II. Etiology was degenerative in 74% of the patients.

RESULTS

Four patients died early for a hospital mortality of 2.1%, and one late death occurred. Two patients with systolic anterior motion required early valve replacement. Two transient episodes of hemiparesis occurred during the first postoperative month. There were no late thromboembolic complications, no late reoperation, and no endocarditis. Mean follow up of 23+/-13 months was complete in 99% of the patients. Seventy-seven patients (40.5%) have had Doppler echocardiography > 1 year after surgery: 61 (80%) of them have no residual regurgitation, 15 have grade 1+/4+ mitral regurgitation, while 1 has grade 2+/4+ insufficiency. Left ventricular end-diastolic volume index (mL/lm2) decreased from 107.4+/-35.5 preoperatively to 74.2+/-24.4 at last control (p<0.001).

CONCLUSION

The physio annuloplasty ring provided reliable and stable results at medium-term follow-up with a very low incidence of valve-related complications.

[Initial results of mitral valvuloplasty using the Physio-Carpentier-Edwards ring]

The Physio-Carpentier-Edwards ring is a new prosthetic ring developed to allow mitral annuloplasty associating remodelling and flexibility of the native mitral annulus. The object of this study was to assess the feasibility and reliability of mitral valvuloplasty with the Physio ring. Between December 1992 and October 1995, 100 patients with an average age of 56.8 years suffering from mitral insufficiency underwent mitral valvuloplasty with a Physio ring. The mitral insufficiency was degenerative in 94% of cases. The degree of regurgitation was scored 3+ or 4/+4/+ in 94 patients. Mitral valve prolapse was observed in 83 patients. Mitral reconstruction was undertaken using Carpentier's techniques. One patient died in the immediate postoperative period. Two patients were reoperated for valve replacement because of systolic anterior motion (SAM). One patient had SAM which regressed with medical treatment. There were no deaths after the hospital period. There were no late reoperations of thrombo-embolic complications. The average follow-up period was 19 +/- 8 months; 77 patients were followed up for over 1 year and all underwent control Doppler echocardiography. Sixty-one patients had no residual mitral insufficiency: 15 patients had grade 1/4 regurgitation and one patient had grade 2/4 regurgitation. The average mitral valve surface area was 2.8 +/- 0.3 cm2. The average left ventricular end diastolic volume decreased from 186 +/- 59 cm3 before surgery to 129 +/- 37 cm3 at the last control (p < 0.001). The authors conclude that the Physio ring enables reliable and effective mitral valvuloplasty with excellent short term results. The benefits of the flexibility of the Physio ring remain to be evaluated by a randomised trial.

[Indication of mechanical circulatory assistance]

Over the last decade, we have seen considerable progress both in medical treatment of acute and chronic heart failure and in circulatory assist systems, including the first used aorta counter-pulse system. More sophisticated systems have been developed with specific indications recognized by specialized teams. However, in the treatment of chronic heart failure, whether caused by idiopathic dilated cardiomyopathies or ischemic heart disease (frequently improved with coronary revascularization), the nature of the disease in patients hospitalized in intensive care units has greatly changed. There is a net tendency towards hospitalizing older patients who may no longer be reasonable candidates for transplantation. The option of circulatory assist is thus undoubtedly reasonable for these patients due to the lack of a sufficient number of donor organs.

Surgical treatment of asymptomatic and mildly symptomatic mitral regurgitation

OBJECTIVE

The purpose of this study was to review the risk-benefit ratio of mitral valve repair in patients with severe mitral regurgitation and no or mild symptoms.

METHODS

From January 1989 to December 1994, 584 patients were operated on for mitral regurgitation. Of these, 175 patients were in New York Heart Association class I or II with grade 3 to 4 isolated chronic mitral regurgitation. They comprise our study population. Mean age was 51.3 +/- 14.3 years. Principal causes of mitral regurgitation were degenerative in 128 (73%) and rheumatic in 26 patients (15%). Leaflet prolapse was the mechanism responsible for regurgitation in 152 patients (86%). Mitral valve repair was performed in 174 patients, and one patient required initial valve replacement. Mean follow-up was 34.3 +/- 18.8 months.

RESULTS

Three patients died, for an overall mortality of 1.7%. Five patients were reoperated on, for an actuarial freedom from reoperation of 97.0% +/- 0.8% at 5 years. Actuarial freedom from thromboembolism and endocarditis was 96.3% +/- 1.7% and 99.4% +/- 0.6%, respectively, for an event-free survival of 91.0% +/- 2.0% at 5 years. Left atrial diameter decreased from 54.3 +/- 11.6 mm to 43.6 +/- 10.5 mm (p < 0.001). Left ventricular end-systolic and end-diastolic diameters decreased from 40.0 +/- 6.8 mm and 64.8 +/- 7.0 mm to 34.6 +/- 6.7 mm (p < 0.001) and 52.7 +/- 7.4 mm (p < 0.001), respectively. Mean residual mitral regurgitation was 0.44 +/- 0.6.

CONCLUSION

Mitral valve repair for chronic mitral regurgitation in patients having mild or no symptoms was performed with low mortality and morbidity, good valve function, and preserved late left ventricular performance. Early repair may be advocated on the basis of severity of regurgitation and valve repairability, regardless of symptoms.

[Penetrating atheromatous ulcer of the thoracic aorta. Apropos of a case]

The authors report a case of penetrating atheromatous ulceration of the descending thoracic aorta complicated by a haemothorax. Atheromatous ulceration of the aorta is usually observed in elderly hypertensives. It is caused by rupture of the internal elastic layer under an atheromatous plaque extending into the media and resulting in a parietal haematoma of the aorta. Clinically, the differential diagnosis is that of a dissection of the aorta or of fissuration of an atheromatous aneurysm. Nowadays, the investigations of choice are a chest CT scan with injection of contrast and MRI. Transoesophageal echocardiography excludes dissection of the aorta but may miss a direct image of penetrating ulcer when the latter is of small size. The treatment of choice is not established because the natural history of the condition is not well known. Penetrating ulcer would seem to progress slowly to development of an aortic aneurysm. Surgery is mainly reserved for forms complicated by painful recurrences or rupture and for cases involving the ascending aorta.

[Wearable mechanical ventricular support]

Progressive technological developments have permitted clinical use of the wearable Baxter-Novacor left ventricular assist system. The system allows total bypass of the left ventricular function, and recovery of an adequate circulation in patients about in cardiogenic shock. Since the first clinical use, in March 1993, six patients about to die have been supported with a cardiac transplantation. This experience suggests that an acceptable answer to the problem of organ shortage is non available.

Mechanical bridge to transplantation: when is too early? When is too late?

BACKGROUND

Optimal timing of implantation of a mechanical circulatory support system in the treatment of acute cardiogenic shock is still unsettled. The issue has been addressed in a retrospective analysis of a group of 98 patients in cardiogenic shock refractory to medical therapy who were candidates for cardiac transplantation, admitted from 1987 to 1994.

METHODS

The treatment included reinforced inotropic support by addition of phosphodiesterase inhibitors to sympathomimetic agents. The patients who did not improve were immediately brought to the operating room for mechanical circulatory support system implantation.

RESULTS

The overall survival in the group of 28 patients selected for mechanical bridge is 50%. No predictive factors of death or multiorgan failure while on the device could be identified, suggesting a lack of contraindications to mechanical circulatory support system implantation.

CONCLUSIONS

The high death rate in patients maintained on medical therapy because of initial improvement as they are awaiting transplantation suggests the benefit of a rapid semielective implantation of an intracorporeal device.

[Cerebral abscess disclosing tetralogy of Fallot with situs inversus in adulthood]

The authors report the case of tetralogy of Fallot (TOF) associated with situs inversus, the first description of this rare association in a previously asymptomatic adult. A 32 years old chauffeur was admitted to hospital with pyrexia and convulsions due to a left temporo-parietal cerebral abscess which had a favourable outcome. The chest X-ray and Doppler echocardiographic study showed a TOF with a high infundibular stenosis and dextrocardia. Abdominal ultrasonography confirmed a complete situs inversus. The good tolerance was attributed to the equilibrated character of the TOF. The orientation of the heart and the cono-truncal septation occur at different times during embryogenesis. However, there are genetic arguments in favour of the non-fortuitous nature of this association.

[Mechanical assistance of circulation. 42 cases]

OBJECTIVES

Mechanical circulatory support was proposed in patients in cardiogenic shock, as a bridge to cardiac transplantation or weaning. The aim of the present study is an analysis of the first 42 cases.

METHODS

The 42 cases included 31 patients in cardiogenic shock unresponsive to medical therapy, good cardiac transplant candidates, and 11 patients unweanable off ventricular assist, or in shock in the intensive care unit. Results are evaluated in terms of transplantability and hospital survival.

RESULTS

Overall success rate is 67%, ranging from 25% in previously transplanted patients to 46% following acute myocardial infarction and 57% in cardiomyopathy. Age and learning curve played a significative role.

CONCLUSION

These data suggest that mechanical support improves survival in patients in cardiogenic shock. Earlier implantation should improve the patient outcome.

[Adaptation to effort in patients with chronic cardiac insufficiency; study by post-exercise Doppler echocardiography, comparative results with a control population]

Adaptation to exercise was studied by post-exercise Doppler echocardiography in patients with chronic cardiac failure and an apparently healthy control population matched for age. This post-exercise Doppler echocardiographic method initially introduced for the detection of myocardial ischaemia has already been validated in normal subjects for the analysis of haemodynamic changes caused by exercise providing the data is recorded in the first 5 minutes following recovery in the recumbent position. Eleven patients with chronic cardiac failure in NYHA classes II or III with a mean age of 54 +/- 11 years and 6 controls (mean age: 46 +/- 9 years) were investigated. The patients had been stabilised for at least 3 months with a vasodilator and diuretic therapy: the control subjects had no medication. After bicycle ergometry performed to 70% of maximum capacity, the subjects were positioned in the left lateral recumbent position. Doppler echocardiography was then performed in the immediate recovery phase. When compared to the control population, the patients with cardiac failure had a reduced chronotropic reserve, a smaller increase in the parameters of myocardial contractility (maximal aortic velocity, maximal aortic acceleration and left ventricular fractional shortening) without an increase in left ventricular end diastolic dimensions in subjects with severe dilatation under basal conditions (left ventricular end diastolic dimension 69 +/- 3 mm). This result suggests the absence of a Frank-Starling effect. The lack of adaptation of the peripheral vascular system was demonstrated by the lack of reduction of left ventricular end systolic stress, already greatly increased at rest (176 vs 77 +/- 10 g/cm2 for patients, compared with controls; p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Post-exercise Doppler-echocardiographic haemodynamics in idiopathic dilated cardiomyopathy after metoprolol infusion

1. The physiological effects of the acute administration of a beta-adrenoceptor antagonist in patients with idiopathic dilated cardiomyopathy were assessed by performing post-exercise Doppler-echocardiography study. Eleven patients and six control subjects were studied. According to a double-blind randomized protocol, 5 mg of metoprolol or placebo was administered before cycloergometer exercise. 2. In patients, after metoprolol, a significant decrease in heart rate and systolic blood pressure, as well as in peak aortic acceleration and cardiac output, was observed 2 min after exercise. Left ventricular end-diastolic diameter did not change from baseline values either after placebo or metoprolol. In normal subjects, as compared with placebo, a decrease in heart rate and peak aortic acceleration was observed after metoprolol, whereas systolic blood pressure did not change. A similar increase in cardiac output occurred after metoprolol, as compared with placebo, associated with an increase in left ventricular end-diastolic diameter and stroke volume. 3. Post-exercise Doppler echocardiography is a means of assessing haemodynamic changes occurring during exercise in patients with congestive heart failure. Although acute metoprolol administration does not provide beneficial haemodynamic effects, a decrease in the energy requirements of the heart and a faster recovery after exercise may participate in the long-term beneficial action of beta-adrenoceptor antagonists.

Iodine 123-labeled metaiodobenzylguanidine imaging in heart disease

Scintigraphic images of myocardial iodine 123-labeled metaiodobenzylguanidine (MIBG) reflect the relative distribution of adrenergic neurodensity and function in the myocardium. In patients with hypertrophic cardiomyopathy or after infarction, MIBG uptake in hypertrophied myocardium and the infarct-related myocardium was found to be decreased in comparison to blood flow distribution, delineated with thallium 201. Most intriguingly, semiquantitative measurements in patients with congestive heart failure demonstrated reduced myocardial MIBG uptake. This reduction correlated directly with indexes of left ventricular function. Decreases in neuronal density, dysfunction of adrenergic neurons, or chronically elevated circulating norepinephrine levels may account for this diminished myocardial uptake, which, as demonstrated in a pilot study of 90 patients with congestive heart failure, was found to be of predictive value for survival.

[Early constrictive pericarditis after coronary revascularization. Apropos of a case]

The authors report a case of severe constrictive pericarditis occurring 6 weeks after coronary bypass surgery and in the absence of any other predisposing factor. The diagnosis was confirmed by CT scan and cardiac catheterisation which showed signs of a diastole. The patient died despite early surgical reoperation because of the severity of the pericardial fibrosis.

[Extensive coronary dissection after percutaneous transluminal angioplasty. Apropos of a case]

The authors report a rare case of very extensive dissection of the right coronary artery immediately after angioplasty; the lesion was totally asymptomatic. Coronary bypass was performed 4 months later without complications and with a satisfactory result at a 15-month follow-up. Coronary dissection during angioplasty is usually located at the site of dilatation: its incidence varies from 6 to 13 p. 100 depending on the series reported. Facilitating factors are analysed, and the management of this complication is discussed: repeat angioplasty and/or emergency or elective coronary bypass, depending on the presence or absence of coronary thrombosis and symptoms, on the importance of the territory threatened and on the quality of collateral circulation.