Optimal timing of aortic valve replacement for aortic stenosis--are we operating late?

OBJECTIVE: To evaluate the adherence to current guidelines for surgery in patients with aortic valve stenosis. DESIGN: From 1 January 1997 to 31 May 1999, 99 patients were accepted for aortic valve surgery with preserved left ventricular function and normal coronary angiogram. On admission for operation, 20 patients were evaluated regarding symptoms, exercise capacity, and left ventricular morphology and function. RESULTS: There were 14 men and 6 women, mean age 64.3 years. Years from symptom onset varied from 2.1 to 3.2. Dyspnoea was the most common limiting symptom. Thirty per cent of the patients were classified as NYHA IIIB. Physical capacity was reduced to 79% of the expected. Left ventricular hypertrophy was present in 14/20 patients. Left ventricular systolic function was reduced with mean ejection fraction of 0.46. Diastolic dysfunction (E/A ratio <1) was present in 12 patients. CONCLUSION: Many patients accepted for aortic valve replacement due to aortic stenosis show advanced disease and are referred for surgery later in the disease process than is recommended in the current guidelines.

Beat-to-beat QRS amplitude variability in elite endurance athletes.

Results from variance electrocardiography, displaying the wide-band, phase-locked electrical micro-variability during the depolarization phase, was analysed versus clinical data, echocardiographic structural and functional variables and myocardial scintigraphic findings in 174 elite orienteers compared with 37 age-matched elite endurance athletes and 50 age-matched, healthy medical students. PCA analysis identified a subgroup of five orienteers deviating from the rest of the study group and both control groups with regard to their QRS amplitude variability. No correlations were found between pathology by medical history or any of the echocardiographic and scintigraphic variables or by the variance electrocardiographic aberrations in any of the groups studied.

Left ventricular hypertrophy is associated with an attenuated endothelium-dependent vasodilation in hypertensive men.

To investigate the relationship between left ventricular hypertrophy (LVH) and endothelium-dependent vasodilation (EDV), 30 untreated hypertensive patients, 18 treated hypertensives (53 +/- 7 years, all males) and 26 age-and sex-matched healthy normotensive controls, underwent evaluation of EDV and endothelium-independent vasodilation (EIDV) in the forearm, by means of local intra-arterial infusions of methacholine (MCh, evaluating EDV) and sodium nitroprusside (SNP, evaluating EIDV). Forearm blood flow was measured by venous occlusion plethysmography and LVH was measured by echocardiography. The reduction in forearm vascular resistance during MCh infusion (4 microg/min) was significantly smaller in the hypertensive patients with LVH when compared to those without LVH, both in the untreated (-61 +/- 12%, n = 19 vs -72 +/- 4%, n = 11, p < 0.01) and in the treated group (-60 +/- 15%, n = 11 vs -75 +/- 5%, n = 7, p < 0.01). Thereby, EDV was significantly impaired only in the hypertensive patients with LVH when compared to controls (-77 +/- 7% at MCh 4 microg/min, p < 0.001). EIDV was not significantly different between patients with and without LVH and controls. In conclusion, the presence of LVH was related to endothelial dysfunction, both in untreated and treated hypertensive patients, suggesting either a role for endothelial function in the development of LVH, or that a dysfunctional endothelium and LVH are coexisting markers of a more severe hypertensive disease.

A 10-year retrospective study of infective endocarditis at a university hospital with special regard to the timing of surgical evaluation in S. viridans endocarditis.

A total of 154 episodes of infective endocarditis (IE) in 149 patients were studied retrospectively with special regard to the major aetiological groups and the surgical evaluation. There were 136 episodes of native valve endocarditis (NVE) (88%) and 18 episodes of prosthetic valve endocarditis (PVE) (12%). Three major groups of NVE crystallized: Streptococcus viridans in 37 (27%), Staphylococcus aureus in 39 (29%) and culture negative IE in 28 (21%) episodes. In these groups surgery during the active phase was required in 41, 28 and 18%, respectively. At the operation myocardial abscess was found in as many as 7/15 cases with S. viridans, but in only in 3/11 cases with S. aureus and 1/5 cases with culture negative IE. The mean duration of preoperative antibiotic treatment was 34 d. This long period of unsuccessful pharmacotherapy, preceded by a mean of 47 d from start of symptoms to admission to hospital, has probably resulted in the high frequency of myocardial abscess in S. viridans NVE. Surgical evaluation should be considered when fever persists beyond 10 d of adequate treatment, even in the absence of clinically apparent complications. Among the PVE episodes, 11/18 were managed with pharmacological treatment alone. Uncomplicated PVE may thus often be successfully treated with antibiotics alone.

An echocardiographic study of right and left ventricular adaptation to physical exercise in elite female orienteers.

BACKGROUND: A considerable body of echocardiographic studies has described how athletic training induces morphological adaptation of the left ventricle in male endurance athletes, but only a few studies have described left ventricular adaptation in female endurance athletes. In contrast to changes in the left ventricle far less attention has been directed towards right ventricular changes due to extensive physical exercise. The purpose of this study was to obtain normal values and to determine if there are any differences in right and left ventricular cavity and wall dimensions between female orienteers and females with a mainly sedentary lifestyle. METHODS: Echocardiography was performed in 42 highly trained elite female orienteers and 32 healthy female students with a predominantly sedentary lifestyle. The 74 females had no history of cardiac disease, a normal electrocardiogram and showed no echocardiographic abnormalities. M-mode and two-dimensional measurements of the right and left ventricular cavity and wall were obtained in elite orienteers and sedentary females. For the right ventricle and wall, multiple cross-sections were used and measurements were obtained from the right ventricular inflow and outflow tract. RESULTS: The left ventricular end-diastolic cavity dimension and the left ventricular wall thickness were significantly greater in the athletes compared with the sedentary controls. The right ventricular inflow tract measurements were all significantly greater in the orienteers compared with the controls but the right ventricular outflow tract measurements were comparable in the study groups. The right ventricular wall thickness, calculated as the mean of three different wall measurements was an average of 13% greater in the athletes compared with the sedentary controls. CONCLUSION: This study suggests symmetrical cardiac enlargement with a concomitant increase in both the right and left ventricular wall, probably reflecting the increased haemodynamic loading in the female athletes.

An echocardiographic study of right ventricular adaptation to physical exercise in elite male orienteers.

Considerably more publications appear on left ventricular morphology than on the right ventricle. The reasons for this imbalance are related to the complex shape of the right ventricular cavity and its position beneath the sternum, making imaging, measurement and functional assessment much more complex than the left ventricular chamber. Little attention has been directed towards right ventricular changes because of training, therefore the present study was designed to assess right ventricular changes due to extensive training by comparing cavity and wall dimensions in 29 sedentary men (mean age 23 years) and 82 elite male orienteers (mean age 22 years). The elite orienteers had on average significantly larger right ventricular outflow (10%) and right ventricular inflow (12%) tract 2 and 3 dimensions. The right ventricular wall measurements were on average 13% larger in the orienteers than the sedentary men. The right ventricular enlargement in endurance athletes probably reflects the increased haemodynamic loading that is caused by prolonged and extensive physical training. The thicker right ventricular wall in endurance athletes increases the contractile reserve and decreases wall stress in the right ventricle.

Pericarbon pericardial valve prosthesis: midterm results of the aortic valve replacement.

This clinical study was undertaken to verify the encouraging results of experimental studies regarding a new pericardial bioprosthesis. From May 1989 to November 1993, 204 patients underwent an aortic valve replacement with the Pericarbon (Sorin Biomedica Cardio S.p.A., Saluggia, Italy) prosthesis. A follow-up was 100% complete and extended to 65 months (total 408 patient-years, average 2.0+/-1.4 years). Mean age at the operation was 75.1+/-5.5 years and 96% were in NYHA clinical stage III or IV. There were 86 men and 118 women; 73 patients had an isolated aortic valve disease, 131 had a concomitant cardiosurgical procedure (coronary artery bypass grafting in 106 patients). The operative mortality (30-day mortality) rate was 11.8% (24/204). There were 24 late deaths (5.9+/-1.2% patient-year). The actuarial probability of survival was 68+/-5% at 5 years. Four patients died of valve-related causes (one thromboembolic complication, two endocarditis, one anticoagulant-related hemorrhage). Actuarial rate of freedom from valve-related death was 95+/-3% at 5 years. Valve-related morbidity included seven thromboembolic episodes (1.7% patient-year), four anticoagulant-related complications (0.9% patient-year), three endocarditis (0.7% patient-year) and one reoperation (0.2% patient-year). After 5 years freedom from thromboembolic events was 83+/-7%, from anticoagulant-related hemorrhage 96+/-2%, from endocarditis 97+/-2%, and from reoperation 99+/-1%. Echocardiographic study performed in 30 patients showed a paraprosthetic leak in four patients, a central leak in two, and cusp thickening in another three. The clinical data showed that the Pericarbon prosthesis has valve-related morbidity. The echocardiographic results suggest that the prosthesis can undergo a pathologic process during the first 5 years after implantation. This makes it necessary to continue the follow-up and include the larger number of patients in the echocardiographic investigation.

Long-term follow up study on 64 elderly patients after balloon aortic valvuloplasty.

BACKGROUND AND AIMS OF THE STUDY: The aims of this study were to evaluate symptomatic improvement and event-free/overall survival after balloon aortic valvulotomy in patients with significant sclerotic aortic valve stenosis. METHODS: Sixty-four patients with calcified aortic stenosis, in NYHA class III-IV, and of mean age 79.0 years, underwent a total of 75 scheduled attempts at balloon aortic valvulotomy, with single balloon catheters between December 1987 and June 1993. Patients were either considered as poor surgical candidates or themselves preferred such valvulotomy. RESULTS: Periprocedural major complications, including death in 6%, occurred in association with 16% of the procedures. Among 57 patients in whom initial dilatation was successful, the average period of symptom relief was 9.4 months (median 7.0, range: 0 to 47 months). Independent predictors for longer duration of symptom relief and survival were systolic arterial pressure > 115 mmHg and female gender; ejection fraction > or = 30% was only predictive of survival. Actuarial survival rates at one, two and three years were 77, 48 and 36% respectively. CONCLUSIONS: Balloon aortic valvulotomy is followed by a short period of symptomatic relief and carries a low periprocedural mortality, but considerable morbidity. By comparison, aortic valve replacement patients aged over 70 and with serious physical limitations (NYHA class IIIB-IV) showed much better overall survival. As contraindications to surgery are in most cases relative, aortic valve replacement should always be considered as the only choice in the surgical decision-making.

An echocardiographic study comparing male Swedish elite orienteers with other elite endurance athletes.

Between 1979 and 1992, there were 16 known cases of sudden unexpected cardiac death among young Swedish orienteers, whose autopsies showed myocarditis to be a common finding. Therefore, 96 elite orienteers and 47 controls underwent echocardiography, showing left ventricular wall motion abnormalities in 9% of the orienteers compared with 4% in the controls.

Echocardiographic right and left ventricular measurements in male elite endurance athletes.

Echocardiography was used to assess normal values in the right and left ventricular cavity and wall in 127 male elite endurance athletes. M-mode and two dimensional measurements of left ventricle and left and right atria were also obtained. All subjects were high-performance orienteers, cross-country skiers and middle-distance runners. They all had a normal electrocardiogram at rest and no echocardiographic evidence of heart disease. With the use of multiple right ventricular cross-sections and two-dimensional measurements, we found a significantly greater right ventricular inflow tract and right and left atrial measurements in endurance athletes compared with earlier studies of normal, active subjects. The right ventricular free wall was slightly thicker than reported in normal active subjects but the differences were small. Left ventricular diastolic diameter was consistent with previous reports of endurance athletes. Of the 127 subjects, 13% had left ventricular wall thickness above 13 mm but none of the athletes had wall thickness above 15 mm. These data suggest that cardiac enlargement occurs symmetrically in both right and left cavities, probably reflecting increased haemodynamic loading, a mechanism by which athletes sustain a high cardiac output during exercise.

Transoesophageal echocardiography and acoustic quantification in assessing regional left ventricular wall motion.

Acoustic Quantification (AQ) is a technique based on analysis of ultrasonic integrated backscatter. It enables a real time detection of blood-tissue borders and numbers the end-diastolic and end-systolic areas throughout the cardiac cycle. AQ added to the 2D image therefore offers an on-line estimate of global ventricular function in the operating room. Since AQ is dependent on a good 2D image as well as adjustment of both transmit- and time gain control the question arises whether this leads to a different assessment, compared to the 2D image only, of off-line assessment of regional left ventricular wall motion (LVWM). Twenty-three consenting patients scheduled for elective coronary bypass grafting were studied. A total of 31 observations were performed and divided into 21 short axis and 10 three chamber long axis views. Regional LVWM score was assessed off-line (video recordings postoperatively) by two independent readers on two occasions. There was no intra-reader difference in assessment of regional LVWM in the short axis view when AQ was added to the 2D image. On the other hand, the interreader difference was highly significant both without and with AQ (P = 0.0001) in this view. In the long axis view the intra-reader difference was significant (P = 0.0008 and P = 0.004 respectively), while the inter-reader difference was non-significant. However, the overall intra-reader and inter-reader agreement was 78% or higher except for the intra-reader difference in the long axis view.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic analysis of cardiac function during high PEEP ventilation.

OBJECTIVE: Does positive end-expiratory pressure ventilation (PEEP) deteriorate cardiac contractility? DESIGN: By means of echocardiography nine piglets were studies during ventilation with 0, 15 and 25 cmH2O (PEEP). Recordings were made before and after 500 ml of 6% dextran 70. MEASUREMENT AND RESULTS: Right and left ventricular end-diastolic diameters were plotted against the stroke volume determined by the thermodilution technique. By combining observations made before and after volume expansion during the different ventilation modes, a ventricular function curve was obtained. The slopes of the curves were similar during all three ventilation modes, both on the left and on the right side. CONCLUSION: This study indicates undisturbed myocardial contractility during PEEP ventilation. We infer that the cardiac output deterioration in the intact animal is caused entirely by impairment of venous return.

Mitral valve prosthetic implantation with preservation of native mitral valve apparatus.

To avoid postoperative morbidity and mortality often associated with left ventricular dysfunction after mitral valve replacement (MVR) for chronic mitral insufficiency, reconstruction or preservation of the native mitral valve apparatus may be attempted during mitral prosthetic implantation (MPI). The effects of mitral surgery on heart function, studied with echocardiography and radionuclide angiography, were compared in seven patients with MPI (study group) and five with MVR (control group) who underwent complete preoperative, early postoperative and 3-6 months follow-up examinations. Preoperatively there was significant intergroup difference only in right ventricular ejection fraction measured at radionuclide angiography, which was lower in the MPI group (p < 0.05). At follow-up the MPI group had improved as regards this fraction (p < 0.005) and stroke volume index (p < 0.05). The number of patients with improved NYHA class at follow-up was significantly greater in the MPI group. Our preliminary experience with preservation of the native mitral valve apparatus thus suggests that the method offers haemodynamic advantages for postoperative right ventricular function.

Non-invasive assessment of systolic left ventricular function in systemic sclerosis.

Systemic sclerosis is a multisystemic disorder, also affecting the heart. To evaluate its influence on systolic left ventricular (LV) function, we investigated 30 consecutive patients (age 54.5 +/- 2.4 years, 15 men and 15 women) and 48 controls matched for age and sex. All subjects were investigated by phonocardiography, pulse curve recordings, M-mode echocardiography, and by pulsed and continuous wave Doppler. Heart rate, blood pressure and peripheral resistance did not differ, but patients weighed less than controls (P less than 0.01). Systolic time intervals indicated systolic impairment, with an increased pre-ejection period to LV ejection time (LVET) ratio (0.37 +/- 0.02 vs 0.30 +/- 0.01 P less than 0.001), and also an increased isovolumic contraction time to LVET ratio (0.17 +/- 0.02 vs 0.12 +/- 0.01, P less than 0.02). The latter difference remained when LVET was adjusted for heart rate. Echocardiographic E-point to septal separation was increased in patients (8.3 +/- 1.3 vs 4.8 +/- 0.3 mm, P = 0.001), also after adjustment for LV dimension (P = 0.0001), while septal fractional thickening was decreased (P less than 0.01). End systolic wall stress (P = 0.0002) and stress to volume ratio (P = 0.03) were lower in systemic sclerosis. Peak LV emptying rate was also lower in the patient group when measured by echocardiography (P = 0.03). There was no difference between groups regarding LV dimensions, fractional shortening or mean velocity of circumferential fibre shortening. While aortic Doppler peak emptying rate did not differ between groups, it occurred later in systole in the patient group (P less than 0.01) as did peak velocity (P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical treatment of carcinoid heart disease.

Right heart failure in patients with carcinoid heart disease is a serious prognostic sign. Consideration and adequate timing of valvular operations seem essential for the postoperative outcome. Without any relation to duration or progression of the metastasizing tumor disease, right heart failure developed and increased rapidly for a period of 12 to 17 months in four patients with classic carcinoid syndrome. Invasive hemodynamic and cardiac ultrasound investigations revealed severe carcinoid heart disease, and medical decompensation treatment gradually failed. Tricuspid and pulmonic valve replacement operations resulted in dramatic improvement in three of the patients, and these patients were still free of cardiac symptoms 10, 12, and 38 months postoperatively. One patient died 5 days postoperatively probably of septicemia. The preoperative and postoperative development of the cardiac disease is evaluated clinically, by cardiac ultrasound and plasma atrial natriuretic peptide concentrations, and related to the tumor disease. Surgical anatomy and operative technique are reported, and the beneficial value of prophylactic treatment of the effects of tumor-released vasoactive substances by a somatostatin analog is emphasized.

Transoesophageal echocardiography improves the diagnostic value of cardiac ultrasound in patients with carcinoid heart disease.

Transthoracic and transoesophageal cardiac echocardiography and Doppler investigations were performed in 31 consecutive patients with malignant midgut carcinoid tumours. The transoesophageal images allowed measurement of the thickness of the atrioventricular valve leaflets and the superficial wall layers on the cavity side of both atria. The mean thickness of the anterior tricuspid leaflet was significantly greater than that of the mitral valve--a difference not seen in a control group of age-matched patients without carcinoid tumours and with normal cardiac ultrasound findings. In addition, the edges of the tricuspid leaflets were thickened giving them a clubbed appearance. Tricuspid incompetence was detected transoesophageally in 71% of the patients with carcinoid compared with 57% by transthoracic investigation. The inner layer of the right atrial wall in the carcinoid patients was significantly thicker than that of the left atrium and that of both atria in the controls. Furthermore, patients with other signs of severe carcinoid heart disease had significantly thicker mean right atrial luminal wall layer than those with less or no signs of right heart disease. Transoesophageal cardiac ultrasound investigation improved the diagnostic accuracy and seemed to show the structural changes typical of carcinoid heart disease established by histopathological investigations.