Reference Doppler echocardiographic values for St. Jude Medical, Omnicarbon, and Biocor prosthetic valves in the aortic position

Effective valve opening area in the detection of dysfunctional aortic valve prostheses: a differentiated statistical analysis of this parameter including the introduction of minimal expected normal values as borderline to dysfunctional stenotic prostheses

BACKGROUND

Dysfunction of heart valve prostheses (VP) is a life-threatening complication and the diagnosis remains difficult. The motivation for this study was to improve the detection of dysfunctional VP by optimizing application of the prosthetic effective orifice area (VA). For this reason the minimal expected normal VA (VA(expected)) was introduced.

METHODS

We investigated echocardiographically 1,369 normally functioning aortic valve prostheses (AVP). Mean VA, transprosthetic peak (PPG) and mean pressure gradients (MPG) were evaluated to gain reference values depending on prosthetic size and construction principle. Mean VA(expected) was calculated by applying a simple formula that was developed empirically using statistical analyses. The results were compared with those of 65 dysfunctional AVPs.

RESULTS

VA(expected) can be applied as a threshold between normal and dysfunctional stenotic AVP and showed a correct estimation in 87% of all normally functioning and 100% of dysfunctional stenotic VPs. The sensitivity for all prosthetic sizes is 1.0, independently of the constructional principle of the VP. Specificity ranged between 0.8 and 1.0, dependent on VP size. The formula representing VA(expected) is simple and can be executed easily.

CONCLUSION

As nearly independent of stroke volume and in consideration of VA(expected), VA seems to have become one of the preferable parameters for detecting pathological stenotic AVPs echocardiographically. The additional application of PPG/MPG and other parameters permits prostheses with relevant isolated regurgitation and patient-prosthesis-mismatch to be distinguished.

Doppler haemodynamics and effective orifice areas of Edwards SAPIEN and CoreValve transcatheter aortic valves

AIMS

Transcatheter aortic valve implantation (TAVI) is a new therapy for severe aortic stenosis in high-risk patients. So far, no reference values for the echocardiographic assessment of this new class of heart valves have been established. The aim of our study was to determine Doppler haemodynamics and the effective orifice area (EOA).

METHODS AND RESULTS

We retrospectively analysed the earliest transthoracic echocardiographic examinations of 146 stable patients after successful TAVI (median 8±20 days). Doppler examinations were analysed for peak instantaneous velocity, peak, and the mean systolic gradient. EOA was determined using the continuity equation. Patients with severe paravalvular aortic or mitral valve regurgitation were excluded. The overall peak instantaneous velocity (n=146) was 2.0±0.4 m/s with a peak systolic gradient of 17.1±7.4 mmHg and a mean gradient of 9.3±4.5 mmHg. The mean EOA was 1.82±0.43 cm2 with an indexed EOA of 1.0±0.27 cm2/m2. In general, all prostheses showed similar values-with the exception of the Edwards Sapien 23 mm which was associated with higher velocities and peak pressure gradients.

CONCLUSION

Our study establishes the normal range for Doppler haemodynamics of four transcatheter aortic valve prostheses. Compared with previously published data of surgically implanted bioprostheses percutaneous valves tend to have similar EOA values but lower mean peak velocities and pressure gradients. In comparison with physiological haemodynamics; however, this new class of heart valves is still associated with a mild obstruction.

Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these techniques sometimes fail to determine the specific cause of PHV dysfunction, which is crucial to the selection of the appropriate treatment strategy. Multidetector-row CT (MDCT) can be of additional value in diagnosing the specific cause of PHV dysfunction and provides valuable complimentary information for surgical planning in case of reoperation. Cardiac magnetic resonance imaging (CMR) has limited value in the evaluation of biological PHV dysfunction. In this Review, we discuss the use of established imaging modalities for the detection of left-sided mechanical and biological PHV dysfunction and discuss the complementary role of MDCT in this context.

Noninvasive imaging of prosthetic cardiac devices

The major advances in cardiovascular care can be linked to the combined growth of advanced imaging modalities and the variety of treatment options available for patients with complex structural, acquired and congenital, valvular, myocardial and aortic diseases. Paralleling this growth are the number and spectrum of complications - such as device failures and infections - that these patients will inevitably encounter. The keys to successful implementation of advanced cardiac therapy are the real-time images, 3D reconstructions, and the hemodynamic and tissue profiles that can be obtained to evaluate these patients and their devices. We will review the roles of echocardiography, multidetector computed tomography and MRI in the evaluation of normal and abnormal cardiac device function.

Early Doppler-echocardiography evaluation of 597 prosthetic aortic valves

OBJECTIVES

This study was designed to describe the Doppler-echocardiography normal values in the early postoperative phase for Carpentier-Edwards Perimount Aortic Heart Valve bioprosthesis (CEP), St. Jude Medical (SJM) or Medical Regent (SJMR) Mechanical Heart Valves, evaluated by a single experienced echo-laboratory.

METHODS

Five hundred and ninety-seven consecutive patients in our hospital, who had had a CEP, a SJM or SJMR-17 mm implanted due to aortic stenosis, underwent a control Doppler-echocardiography evaluation 4-7 days after surgery. Hemodynamic performance of SJM, SJMR and CEP were accurately described, evaluating flow-dependent (trans-prosthetic velocities and gradients) and flow-independent (effective orifice area, indexed effective orifice area and Doppler velocity index) Doppler-echocardiography parameters.

RESULTS

Of the 597 patients 50.6% were women (n = 302). Mean age was 66.3 +/- 11.7 years. Mean body surface area (BSA) was 1.76 +/- 0.22 m. Mean ejection fraction was 55.3 +/- 10.3%. Two hundred and sixty CEPs and 337 St. Jude mechanical valves (301 SJM and 36 SJMR size-17) were implanted. Comparing size-by-size SJM to CEP, the former were basically less flow obstructive.

CONCLUSION

Our data confirm the wide range of variability, pointing out the need to perform routinely an accurate baseline Doppler-echocardiography evaluation of the hemodynamic profile of prosthetic aortic valves, including flow-dependent and independent parameters, to allow an adequate interpretation at follow-up.

Prosthetic heart valves: Types and echocardiographic evaluation

In the last five decades multiple different models of prosthetic valves have been developed. The purpose of this article is to provide a comprehensive source of information for the types and the echocardiographic evaluation of the prosthetic heart valves.

Prosthesis-Patient Mismatch is Associated with Higher Operative Mortality Following Aortic Valve Replacement

BACKGROUND

Prosthesis-patient mismatch (PPM) occurs when the valve prosthesis implanted at surgery is too small in relation to patient's body size, causing high transvalvular gradients. We investigated if severe PPM is related to early morbidity and mortality after aortic valve replacement (AVR).

METHODS

We analysed prospectively collected data of 701 consecutive patients undergoing AVR between June 2001 and February 2006 at two Australian public hospitals. The indexed valve effective orifice area (IEOA) was estimated for each valve prosthesis implanted. PPM was defined as <or=0.65 cm2 m(-2). PPM was correlated with operative mortality, stroke, prolonged ventilation, new renal failure, prolonged intensive care stay, prolonged hospital stay and readmission to hospital within 30 days by univariate and multivariate methods.

RESULTS

PPM was present in 6.6% of patients. Overall operative mortality was 4.1%. Isolated AVR was performed in only 38.4% of patients. For patients with PPM, the univariate and multivariate odds ratio for mortality were 5.2 (P=0.002) and 6.1 (P=0.006), respectively. The other multivariate predictors of mortality were age, pre-operative serum creatinine, emergency status, pulmonary artery pressure and bypass time. PPM was not associated with stroke, prolonged ventilation, new renal failure, prolonged intensive care or hospital stay, or readmission within 30 days.

CONCLUSION

PPM was associated with increased operative mortality. PPM should be avoided where possible as it may reduce operative mortality following AVR.

Left ventricular diastolic dysfunction late after aortic valve replacement in patients with aortic stenosis

Patients with severe aortic stenosis (AS) are known to have increased left ventricular (LV) mass and diastolic dysfunction. It has been suggested that LV mass and diastolic function normalize after aortic valve replacement (AVR). In the present study, change in LV mass index and diastolic function 10 years after AVR for AS was evaluated. Patients who underwent AVR from 1991 to 1993 (n = 57; mean age 67 +/- 8.6 years at AVR, 58% men) were investigated with Doppler echocardiography preoperatively and 2 and 10 years postoperatively. Diastolic function was evaluated by integrating mitral and pulmonary venous flow data. Expected values for each patient, taking age into consideration, were defined using a control group (n = 71; age range 18 to 83 years). Patients were classified into 4 types: normal diastolic function (type A), mild diastolic dysfunction (type B), moderate diastolic dysfunction (type C), and severe diastolic dysfunction (type D). There was a reduction in LV mass index between the preoperative (161 +/- 39 g/m2) and 2-year follow-up (114 +/- 28 g/m2) examinations (p <0.0001), but no further reduction was seen at 10 years (119 +/- 49 g/m2). The percentage of patients with increased LV mass index decreased from 83% preoperatively to 29% at 2-year follow-up (p <0.001). The percentage of patients with moderate to severe LV diastolic dysfunction (types C and D) was unchanged between the preoperative (7%) and 2-year follow-up (13%) examinations (p = 0.27). The percentage of patients increased at 10-year follow-up to 61% (p <0.0001). In conclusion, this reveals the development of moderate to severe diastolic dysfunction 10 years after AVR, despite a reduction in the LV mass index.

St. Jude Medical Toronto biologic aortic root prosthesis: Early FDA phase II IDE study results

BACKGROUND

Several biological aortic root replacement techniques have distinct advantages over mechanical composite root replacement including better valvular hemodynamic characteristics and the lack of need for anticoagulation. Current biological root replacement options lack proven long-term durability or are limited by technical or practical concerns. We report the early results from a phase II multicenter clinical trial of the porcine St. Jude Toronto Bioprosthesis with BiLinx (Toronto root).

METHODS

176 Toronto roots were implanted as total aortic root replacement from August 2001 through August 2003. Concomitant cardiac procedures including coronary artery bypass grafting (31%) and ascending aortic replacement (55%) were performed in 74%. Patients were followed clinically and were examined with an echocardiogram at discharge, 6 months, 12 months, and yearly thereafter. Root sizes implanted included 29 mm in 38%, 27 mm in 30%, 25 mm in 20%, 23 mm in 10%, and 21 mm in 2.2%.

RESULTS

There are 205 patient years of follow-up through October 2003. Operative mortality was 3.9% (none were valve related) and late mortality was 4%. Operative stroke rate was 1.1% and late stroke rate was 0.6%. Endocarditis developed in 1 patient. Freedom from aortic regurgitation is to date 100% at discharge, 6 months, and 1 year postimplant. Reoperation of the aortic valve/root was not required in any patient. Six-month mean transvalvular gradients for 21-29 mm valves were 12.8, 8.8, 5.3, 4.9, and 4.7 mm Hg, respectively.

CONCLUSIONS

Aortic root replacement with the Toronto root is safe and provides superb transvalvular hemodynamics with freedom from anticoagulation. The Toronto root seems widely applicable for all types of aortic root pathology and these early data offer very encouraging results. Long-term follow-up is required.

A Six-Year Experience with the Omnicarbon Valve in North American Patients

AIM

We studied the results of an all-carbon monoleaflet valve prosthesis (the Omnicarbon) in a North American population.

METHODS

Patients were recalled to our valve clinic for complete evaluation, including echocardiography, laboratory tests, and physician examination. This experience includes 108 Omnicarbon valve implants. We report the results of single aortic (AVR) or mitral (MVR) valve replacement.

RESULTS

Patients' ages ranged from 40 to 83 (mean: 63 +/- 9 years), and most were male (60%, 59/98). Preoperatively, 71% were NYHA Classes III/IV, while most patients are now Classes I/II (86%). AVR predominated (63%, 62/98), and many patients (44%, 43/98) underwent cardiac procedures either previously or concomitant with valve replacement. Hospital mortality was 6.1% (6/98). Predicted hospital mortality using the Parsonnet additive risk model averaged 12.1%. Currently, four patients cannot be located (96% accountability). Overall, hematology indicated low hemolysis-lactate dehydrogenase: 691 +/- 184 IU/L (112%+/- 30% upper normal), reticulocytes: 1.8%+/- 0.7%, and red blood cells (10(6)/mm(3)): 4.41 +/- 0.50 (males)/4.16 +/- 0.50 (females). International normalized ratio averaged 2.67 +/- 0.72. Doppler echocardiography values were acceptable and comparable to other mechanical valves. Five-year survival (hospital death included) is 86%+/- 4%. At 5 years, freedom from any thromboembolic event is 99%+/- 1%, and freedom from bleeding is 97%+/- 2%. Endocarditis and nonstructural dysfuction also occurred at low rates (99%+/- 1% freedom at five years), and no structural failure or hemolytic anemia was observed during the 343 patient-years (mean: 3.7 +/- 1.6 years).

CONCLUSIONS

Good hematology and hemodynamics, along with remarkably low complication rates, demonstrate that the Omnicarbon valve meets contemporary performance expectations.

Early results of a new mechanical tri-leaflet heart valve prosthesis--"Tricusp": an animal study

OBJECTIVE

A new tri-leaflet mechanical heart valve made of titanium was inserted in the mitral position to evaluate early results.

METHODS AND RESULTS

Five sheep were followed between 3 and 6 months (mean 4.7 months) and performed very well clinically during the follow-up period. In three of five animals a minor para-valvular leakage without hemodynamic importance was observed. The invasive pressure measurements at the end of follow-up revealed only minor transvalvular pressure differences between 1 and 4 mmHg (mean 2.4 mmHg). Similar results were obtained by echo-Doppler technique. Histological examination of the tissue around the valve showed no signs of foreign body reaction or chronic inflammatory reaction.

CONCLUSION

This new tri-leaflet heart valve has shown an excellent hemodynamic performance and good tissue compatibility, and therefore may be an alternative to other currently used valve prostheses.

Net pressure gradients in aortic prosthetic valves can be estimated by Doppler

BACKGROUND

In aortic prosthetic valves, both the Doppler-estimated gradients and orifice areas are misleading in the assessment of hemodynamic performance. The parameter of major interest is the net pressure gradient after pressure recovery (PR). We, therefore, investigated, in vitro, our ability to predict the net pressure gradient and applied the formulas in a representative patient population with 2 different valve designs.

METHODS

We studied the St Jude Medical (SJM) standard valve (size 19-27) and SJM Biocor (size 21-27) in an in vitro steady-flow model with simultaneous Doppler-estimated pressure and catheter pressure measurements. Using echocardiography, we also studied patients who received the SJM (n = 66) and SJM Biocor (n = 45).

RESULTS

In the SJM, we observed PR both within the prosthesis and aorta, whereas in the SJM Biocor, PR was only present in the aorta. We estimated the PR within the valve and within the aorta separately from echocardiographic in vitro data, combining a regression equation (valve) with an equation on the basis of fluid mechanics theory (aorta). The difference between estimated and catheter-obtained net gradients (mean +/- SD) was 0.6 +/- 1.6 mm Hg in the SJM and -0.2 +/- 1.9 mm Hg in the SJM Biocor. When these equations were applied in vivo, we found that PR had an overall value of 57 +/- 7% of the peak Doppler gradient in the SJM and 33 +/- 9% in the SJM Biocor.

CONCLUSIONS

The in vitro results indicate that it is possible to predict the net pressure gradient by Doppler in bileaflet and stented biologic valves. Our data indicate that important PR is also present in stented biologic valves.

Thrombogenic influence of biomaterials in patients with the Omni series heart valve: pyrolytic carbon versus titanium

An opportunity to assess the thromboembolic rates caused by the construction materials on valve replacements is possible with the Omni series of mechanical heart valves. The Omnicarbon and Omniscience valves are identical in form but differ in that the Omnicarbon valve is constructed entirely of pyrolytic carbon, whereas the Omniscience valve uses titanium for its housing, the rest of its structure being pyrolytic carbon. The literature was reviewed and a comparison in similar groups of patients was made between these two model valves for their thromboembolic rates in the mitral and aortic positions. A total of 569 aortic Omnicarbon valves (4,146 patient years [pt yrs.1) had a thromboembolic events (T/E rate) of 0.5% compared with 1.7% for 468 aortic Omniscience (1,552 pt yrs); p < 0.0001. A total of 298 mitral Omnicarbon valves (3,333 pt yrs) had a T/E rate of 1.6% compared with 2.6% for 716 mitral Omniscience valves (2,134 pt yrs), p < 0.001. There was no difference in the anticoagulation management between the two model valves although the Omniscience valve required higher prothrombin or International Normalized Rate maintenance levels, which resulted in higher bleeding rates among patients with Omniscience valves.

Assessment of effective orifice area of prosthetic aortic valves with Doppler echocardiography: an in vivo and in vitro study

OBJECTIVES

We sought to evaluate the Doppler assessment of effective orifice area in aortic prosthetic valves. The effective orifice area is a less flow-dependent parameter than Doppler gradients that is used to assess prosthetic valve function. However, in vivo reference values show a pronounced spread of effective orifice area and smaller orifices than expected compared with the geometric area.

METHODS

Using Doppler echocardiography, we studied patients who received a bileaflet St Jude Medical valve (n = 75; St Jude Medical, Inc, St Paul, Minn) or a tilting disc Omnicarbon valve (n = 46; MedicalCV, Incorporated, Inver Grove Heights, Minn). The prosthetic valves were also investigated in vitro in a steady-flow model with Doppler and catheter measurements in the different orifices. The effective orifice area was calculated according to the continuity equation.

RESULTS

In vivo, there was a wide distribution with the coefficient of variation (SD/mean x 100%) for different valve sizes ranging from 21% to 39% in the St Jude Medical valve and from 25% to 33% in the Omnicarbon valve. The differences between geometric orifice area and effective orifice area in vitro were 1.26 +/- 0.41 cm(2) for St Jude Medical and 1.17 +/- 0.38 cm(2) for Omnicarbon valves. The overall effective orifice areas and peak catheter gradients were similar: 1.35 +/- 0.37 cm(2) and 25.9 +/- 16.1 mm Hg for St Jude Medical and 1.46 +/- 0.49 cm(2) and 24.6 +/- 17.7 mm Hg for Omnicarbon. However, in St Jude Medical valves, more pressure was recovered downstream, 11.6 +/- 6.3 mm Hg versus 3.4 +/- 1.6 mm Hg in Omnicarbon valves (P =.0001).

CONCLUSIONS

In the patients, we found a pronounced spread of effective orifice areas, which can be explained by measurement errors or true biologic variations. The in vitro effective orifice area was small compared with the geometric orifice area, and we suspect that nonuniformity in the spatial velocity profile causes underestimation. The St Jude Medical and Omnicarbon valves showed similar peak catheter gradients and effective orifice areas in vitro, but more pressure was recovered in the St Jude Medical valve. The effective orifice area can therefore be misleading in the assessment of prosthetic valve performance when bileaflet and tilting disc valves are compared.

An evaluation of prosthetic aortic valves using transesophageal echocardiography: the double-envelope technique

The conventional continuity equation uses nonsimultaneous measurements of blood flow velocities through the left ventricular outflow tract and across the aortic valve to calculate aortic valve area (AVA). We have noted that both velocities can be simultaneously obtained from continuous wave (CW) Doppler analysis (double-envelope [DE]). We hypothesize that prosthetic AVA can be calculated by using the DE technique, during transesophageal echocardiography (TEE). Prosthetic AVA was calculated in 41 of 45 patients immediately after aortic valve replacement by using the DE/AVA technique. Left ventricular outflow tract diameter was obtained from an esophageal view, while subvalvular (V(1)) and valvular (V(2)) peak velocities were simultaneously obtained from transgastric views by using CW Doppler. Prosthetic AVA and V(1)/V(2) ratio (Doppler velocity index) were calculated. V(1) was also measured by using pulse wave Doppler, as is conventionally done. Twenty-three Carbomedic (CM) and 18 Carpentier-Edwards (CE) AVA were evaluated. DE/AVAs for CM and CE valves correlated and agreed with that reported by the manufacturer (CM r(2) = 0.91, mean bias -0.25 cm(2) [SD 0.18]; CE r(2) = 0.73, mean bias -0.02 cm(2) [SD 0.27]). Calculated Doppler velocity index values agree with available data (mean bias 0.03 [SD 0.05]). The V(1) obtained by using the DE method was nearly identical to the V(1) obtained by using pulse wave (r(2) = 0.95, mean bias 0.02 m/s [SD 0.04 m/s]). TEE assessment of prosthetic AVA using the DE technique agrees with data reported by the manufacturer. Obtaining subvalvular and valvular velocities from the same CW Doppler trace may simplify the continuity equation and help avoid errors caused by beat-to-beat changes in blood flow. Quantitative prosthetic aortic valve assessment can be performed, on-line, with TEE by using the DE technique.

IMPLICATIONS

Quantitative assessment of prosthetic aortic valve area can be performed on-line by using transesophageal echocardiography using the double envelope technique.

Aortic valve replacement: is valve size important?

OBJECTIVE

We sought to determine whether aortic prosthesis size adversely influences survival after aortic valve replacement.

METHODS

A total of 892 adults receiving a mechanical (n = 346), pericardial (n = 463), or allograft (n = 83) valve for aortic stenosis were observed for up to 20 years (mean, 5.0 +/- 3.9 years) after primary isolated aortic valve replacement. We used multivariable propensity scores to adjust for valve selection factors, multivariable hazard function analyses to identify risk factors for all-cause mortality, and bootstrap resampling to quantify the reliability of the results.

RESULTS

Twenty-five percent of patients had indexed internal orifice areas of less than 1.5 cm(2)/m(2) and more than 2 SDs (Z-value) below predicted normal aortic valve size. Mechanical valve orifices were smaller (1.3 +/- 0. 29 cm(2)/m(2), Z = -2.2 +/- 1.16) than pericardial (1.9 +/- 0.36 cm(2)/m(2), Z = -0.40 +/- 1.01) or allograft valves (2.1 +/- 0.50, Z = 0.24 +/- 1.17). The overall survival was 98%, 96%, 86%, 69%, and 49% at 30 days and 1, 5, 10, and 15 years postoperatively. Univariably, survival was weakly and inversely related to manufacturer valve size (P =.16) and internal orifice diameter (P =. 2) but completely unrelated to indexed valve area (P =.6) or Z-value (P =.8). These, and univariable differences among valve types (P =. 004), were accounted for by different prevalences in patient risk factors and not by valve size or type per se. Bootstrap resampling indicated that these findings had a less than 15% chance of being incorrect.

CONCLUSIONS

Survival after aortic valve replacement is strongly related to patient risk factors but appears not to be adversely affected by moderate patient-prosthesis mismatch (down to about 4 SDs below normal). Aortic root enlargement to accommodate a large prosthesis may be required in few situations.

Influence of aortic valve replacement, prosthesis type, and size on functional outcome and ventricular mass in patients with aortic stenosis

OBJECTIVES

Two years after surgery for severe aortic stenosis, we prospectively evaluated the influence of aortic valve replacement, as well as valve type (mechanical or stented biologic) and size, on functional status, left ventricular function, and regression of mass.

METHODS

Patients who received either a mechanical (n = 95) or a biologic valve (n = 42) were studied by echocardiography before the operation and after 2 years.

RESULTS

The percentage of patients with severe dyspnea decreased from 53% to 13% (P =.001). The cardiac index increased from mean 2.6 L/min per square meter (95% CI: 2.48-2. 72 L/min per square meter) to 3.1 L/min per square meter (95% CI: 2. 94-3.26 L/min per square meter; P =.001). The percentage of the patients with mild-to-moderate diastolic dysfunction decreased from 43% to 18% (P =.001). The left ventricular mass index was reduced by 42.4 g (95% CI: 35-50 g; P =.001). In comparison with biologic valves of the same size, mechanical valves produced a more pronounced reduction in mass index (overall difference 21.7 g; 95% CI: 37.1-6.4 g; P =.007) and a lower mean Doppler gradient (overall difference 4 mm Hg; 95% CI: 2-6 mm Hg; P =.0002).

CONCLUSIONS

Patients undergoing aortic valve replacement had an improvement in functional status, as well as systolic and diastolic left ventricular function, and a reduction in left ventricular mass index, irrespective of prosthesis size and type. Mechanical valves are somewhat less obstructive than stented bioprosthetic valves of the same size. They are also associated with a concomitantly more pronounced reduction of left ventricular mass.

Gender differences in patients with severe aortic stenosis: impact on preoperative left ventricular geometry and function, as well as early postoperative morbidity and mortality

OBJECTIVE

In patients with severe aortic stenosis, we studied the impact of gender on preoperative left ventricular geometry and function, as well as on early postoperative mortality and morbidity.

METHODS

Prospective Doppler echocardiographic evaluation was performed in 99 female patients and 96 males.

RESULTS

The patients had severe aortic stenosis and the mean pressure gradients were similar in females and males. Left ventricular diastolic volume adjusted for body surface area (BSA) was larger in males, 55+/-17.4 ml/m2 versus 43+/-13.1 mL/m2 (mean+/-standard deviation; P = 0.0001). The ejection fraction was similar in females (55+/-14%) and males (55+/-13%), and patients of both sexes had significantly lower stroke volume and cardiac index than healthy controls. The relative wall thickness (wall thickness/diastolic diameter ratio) was higher (P = 0.03) in females (0.47+/-0.10) than in males (0.43+/-0.10) Consequently, the diastolic diameter/wall thickness ratio (a substitute for wall tension) was higher (P = 0.02) in males (4.2+/-0.99) than in females (3.9+/-0.80). Compared with survivors, patients who died within 30 days of the operation (n = 17, 11 females) had a smaller body surface area (1.70+/-0.19 vs. 1.82+/-0.19 m2, P = 0.012), smaller left ventricular outflow tract (20.8+/-0.21 vs. 22.0+/-0.22 mm, P = 0.023), higher incidence of abnormal intraventricular flow velocity (33 vs. 8%, P = 0.018) and increased relative wall thickness (0.52+/-0.17 vs. 0.45+/-0.09 P = 0.039). Gender was of no independent importance for early mortality when age and left ventricular outflow tract diameter were accounted for.

CONCLUSIONS

Cardiac adaptation to aortic stenosis seems to be influenced by gender, males presenting larger left ventricular volumes and higher wall tension. The echocardiographic findings of a narrow left ventricular outflow tract, abnormally increased intraventricular velocity and increased relative wall thickness identified patients with increased risk of early postoperative mortality. However gender had no independent impact on early postoperative outcome.