Reverse shoulder arthroplasty: the role of physical therapy on the clinical outcome in the mid-term to long-term follow-up.

INTRODUCTION: Reverse shoulder arthroplasty shifts the rotational center of the shoulder joint caudally and medially to restore shoulder function in a rotator cuff deficient shoulder. Despite promising results in early- and mid-term follow-up, long-term loss in shoulder function has been described in the literature. A lack of exercise in elderly patients may be one reason for this loss in function. This study examines the functional benefits of physical therapy in the mid-term to long-term follow-up regarding the subjective and objective shoulder function. MATERIALS AND METHODS: Twenty patients with a mean age of 73 years were included in this series. The study was performed as a single-center, prospective study. Initial indications for reverse shoulder arthroplasty were cuff tear arthropathy, failed anatomical shoulder arthroplasty, and fracture sequelae. The patients were clinically examined at a mean follow-up of 62 months using the Constant score (CS) and the DASH score for the operated and the non-operated shoulder. They were reevaluated using the same scores following a standardized physical therapy program of 6 weeks' duration. RESULTS: The mean CS as well as the mean age- and gender-adjusted CS of the affected shoulder improved significantly from 53.5 points to 59.3 points, and 72.7-80.8%, respectively. The subcategories activities of daily living and range of motion of the CS improved significantly, whereas no significant improvement was observed for the subcategories pain and strength. Evaluating the contralateral shoulder, no significant change was observed for the age- and gender-adjusted CS and the CS as well as its subcategories. We found no significant difference in the CS comparing the different etiologies prior to physical therapy. DISCUSSION: Physical therapy plays an important role subsequent to reverse shoulder arthroplasty. It also has an effect in the mid-term to long-term follow-up regarding the range of motion as well as activities of daily living. However, physical therapy seems to have limited effect on the strength and the residual pain level. LEVEL OF EVIDENCE: Level III.

Reverse shoulder arthroplasty: the role of physical therapy on the clinical outcome in the mid-term to long-term follow-up.

INTRODUCTION: Reverse shoulder arthroplasty shifts the rotational center of the shoulder joint caudally and medially to restore shoulder function in a rotator cuff deficient shoulder. Despite promising results in early- and mid-term follow-up, long-term loss in shoulder function has been described in the literature. A lack of exercise in elderly patients may be one reason for this loss in function. This study examines the functional benefits of physical therapy in the mid-term to long-term follow-up regarding the subjective and objective shoulder function. MATERIALS AND METHODS: Twenty patients with a mean age of 73 years were included in this series. The study was performed as a single-center, prospective study. Initial indications for reverse shoulder arthroplasty were cuff tear arthropathy, failed anatomical shoulder arthroplasty, and fracture sequelae. The patients were clinically examined at a mean follow-up of 62 months using the Constant score (CS) and the DASH score for the operated and the non-operated shoulder. They were reevaluated using the same scores following a standardized physical therapy program of 6 weeks' duration. RESULTS: The mean CS as well as the mean age- and gender-adjusted CS of the affected shoulder improved significantly from 53.5 to 59.3 points, and 72.7-80.8%, respectively. The subcategories activities of daily living (ADL) and range of motion (ROM) of the CS improved significantly, whereas no significant improvement was observed for the subcategories pain and strength. Evaluating the contralateral shoulder, no significant change was observed for the age- and gender-adjusted CS and the CS as well as its subcategories. We found no significant difference in the CS comparing the different etiologies prior to physical therapy. DISCUSSION: Physical therapy plays an important role subsequent to reverse shoulder arthroplasty. It also has an effect in the mid-term to long-term follow-up regarding the range of motion as well as activities of daily living. However, physical therapy seems to have limited effect on the strength and the residual pain level. LEVEL OF EVIDENCE: Level III.

Echocardiographic Determinants of One-Year All-Cause Mortality in Patients With Chronic Heart Failure Complicated by Significant Functional Tricuspid Regurgitation.

BACKGROUND: Right ventricular (RV) dysfunction plays an important role in chronic heart failure (CHF). We evaluated the echocardiographic determinants of 1-year all-cause mortality in CHF patients with clinically relevant functional tricuspid regurgitation (TR). METHODS AND RESULTS: A total of 101 consecutive CHF patients (mean age 74 ± 10 years, 53% male) with moderate or severe functional TR were enrolled. Each patient underwent at least 2 echocardiography examinations in an interval of >6 months. Clinical follow-up was made after a median of 305 (interquartile range 164-365) days after the last echocardiography. The primary end point was all-cause mortality. Forty-two patients (42%) died during follow-up. Baseline right atrial (RA) area, TR volume increase and RV enlargement over time were significantly higher in nonsurvivors than survivors (all P < .05). Compared to baseline levels, systolic pulmonary artery pressure (sPAP) was significantly reduced in nonsurvivors during follow-up echocardiography (54 ± 19 vs 49 ± 21 mm Hg; P = .010), but significantly increased in survivors (48 ± 17 vs 54 ± 17 mm Hg; P = .001). Multivariable survival analysis suggested that baseline RA area ≥27 cm2 (hazard ratio [HR] 2.41, 95% confidence interval [CI] 1.21-4.80; P = .013), follow-up TR proximal isovelocity surface area regurgitant volume increase ≥15 mL (HR 2.27, 95% CI 1.20-4.31; P = .012), RV middle diameter increase ≥10 mm (HR 2.38, 95% CI 1.10-5.11; P = .027), and sPAP reduction ≥10 mm Hg (HR 3.04, 95% CI 1.51-6.13; P = .002) were determinants of 1-year all-cause mortality after the last echocardiography. Patients with 2 or 3 of these determinants were faced with significantly increased 1-year mortality (88% or 100%). CONCLUSIONS: Dynamic RV morphologic and functional changes during serial echocardiography are associated with significantly increased mortality risk in CHF patients with moderate or severe functional TR.

Cardiac amyloidosis mimicking severe aortic valve stenosis - a case report demonstrating diagnostic pitfalls and role of dobutamine stress echocardiography.

BACKGROUND: Aortic valve stenosis is a common finding diagnosed with high sensitivity in transthoracic echocardiography, but the examiner often finds himself confronted with uncertain results in patients with moderate pressure gradients and concomitant systolic heart failure. While patients with true-severe low-gradient aortic valve stenosis with either reduced or preserved left ventricular systolic function are primarily candidates for valve replacement, there is a relevant proportion of patients with pseudo-severe aortic valve stenosis anticipated not to benefit but actually rather deteriorate by interventional therapy or surgery. CASE PRESENTATION: In this article we present a case report of a male patient with pseudo-severe aortic valve stenosis due to cardiac amyloidosis highlighting the diagnostic schedule. The patient underwent stress echocardiography because of discrepant findings in transthoracic echocardiography and cardiac catheterization regarding the severity of aortic valve stenosis. After evaluation of the results, it became clear that he had a need for optimum heart failure medication and implantation of a cardiac resynchronization therapy defibrillator. CONCLUSION: Due to the pitfalls in conventional as well as invasive diagnostics at rest, Stress echocardiography should be considered part of the standard optimum diagnostic spectrum in all unclear or borderline cases in order to confirm the correct diagnosis and constitute optimal therapy.

Systematic Echocardiographic Evaluation of Mitral Valve Regurgitation for Transcatheter Edge-to-Edge Repair.

In patients with relevant mitral regurgitation (MR), transcatheter edge-to-edge repair (also called MitraClip) provides an alternative treatment option especially for inoperable or high-risk patients. In preparation for the procedure, echocardiography is the method of choice for assessment of mitral valve (MV) morphology and function and thus provides important information if successful treatment of MR can be accomplished by MitraClip. This review article provides structured and detailed guidance how to systematically assess functional and degenerative MR and MV pathology by echocardiography in order to select eligible patients for this procedure. Furthermore, it highlights state-of-the-art echocardiographic methods and potential pitfalls in patient selection.

Interference with ERK(Thr188) phosphorylation impairs pathological but not physiological cardiac hypertrophy.

Extracellular signal-regulated kinases 1 and 2 (ERK1/2) are central mediators of cardiac hypertrophy and are discussed as potential therapeutic targets. However, direct inhibition of ERK1/2 leads to exacerbated cardiomyocyte death and impaired heart function. We have previously identified ERK(Thr188) autophosphorylation as a regulatory phosphorylation of ERK1/2 that is a key factor in cardiac hypertrophy. Here, we investigated whether interference with ERK(Thr188) phosphorylation permits the impairment of ERK1/2-mediated cardiac hypertrophy without increasing cardiomyocyte death. The impact of ERK(Thr188) phosphorylation on cardiomyocyte hypertrophy and cell survival was analyzed in isolated cells and in mice using the mutant ERK2(T188A), which is dominant-negative for ERK(Thr188) signaling. ERK2(T188A) efficiently attenuated cardiomyocyte hypertrophic responses to phenylephrine and to chronic pressure overload, but it affected neither antiapoptotic ERK1/2 signaling nor overall physiological cardiac function. In contrast to its inhibition of pathological hypertrophy, ERK2(T188A) did not interfere with physiological cardiac growth occurring with age or upon voluntary exercise. A preferential role of ERK(Thr188) phosphorylation in pathological types of hypertrophy was also seen in patients with aortic valve stenosis: ERK(Thr188) phosphorylation was increased 8.5 ± 1.3-fold in high-gradient, rapidly progressing cases (≥40 mmHg gradient), whereas in low-gradient, slowly progressing cases, the increase was not significant. Because interference with ERK(Thr188) phosphorylation (i) inhibits pathological hypertrophy and (ii) does not impair antiapoptotic ERK1/2 signaling and because ERK(Thr188) phosphorylation shows strong prevalence for aortic stenosis patients with rapidly progressing course, we conclude that interference with ERK(Thr188) phosphorylation offers the possibility to selectively address pathological types of cardiac hypertrophy.

Clinical performance of lateralized versus non-lateralized reverse shoulder arthroplasty: a prospective randomized study.

BACKGROUND: Reverse shoulder arthroplasty (RSA) is an established therapeutic option in the treatment of cuff tear arthropathy (CTA). Recent studies have described a positive effect of lateralization of the center of rotation, especially on postoperative rotational function. The goal of this study is to compare the outcome of non-lateralized versus lateralized RSA with particular regard to rotational function in patients with CTA. METHODS: Thirty-four patients underwent implantation of RSA either with lateralization (n = 17) or without lateralization (n = 17) by use of a 1-cm autologous bone graft ("bony increased offset") of the humeral head for CTA. Clinical outcomes were measured with the Constant score; the Disabilities of the Arm, Shoulder and Hand score; and the Activities of Daily Living Requiring External Rotation score, as well as measurement of external rotation and determination of the external rotation lag sign with the arm at the side and at 90° of abduction, at 1 year postoperatively and at final follow-up. Computed tomography scan evaluation was performed in all patients preoperatively and at 1 year postoperatively to assess preoperative fatty infiltration of the rotator cuff and bony integration of the graft postoperatively. RESULTS: At final follow-up, all patients showed significantly increased functional results. There were no significant differences in the evaluated parameters. If patients with degenerative changes of the teres minor were excluded, the lateralized group showed significantly increased external rotation. Bony integration of the graft could be verified on postoperative computed tomography scans in all patients. CONCLUSION: RSA with bony lateralization shows a trend toward improved external rotation in lateralized RSA, with a statistically significant improvement in external rotation in patients with an intact teres minor.

The metaphyseal bone defect predicts outcome in reverse shoulder arthroplasty for proximal humerus fracture sequelae.

Reverse shoulder arthroplasty (RSA) represents an established procedure for treatment of fracture sequelae (FS) after proximal humerus fractures. The present work evaluates which factors are of influence for the clinical outcome. Fifty cases (mean age 69, range 44-89) have been evaluated postoperatively clinically [Constant Score (CS)] and radiographically (mean FU 34; range 24-93 months). The type of primary treatment, the amount of a metaphyseal bone defect, the preoperative status of the rotator cuff, the number of previous operative interventions and the type of FS according to Boileau were analysed whether they are of influence for clinical outcome. The mean CS increased significantly from 16.9 ± 6.7 preoperatively to 54.1 ± 15.7 points postoperatively. The CS of primary conservative treatment was significantly higher in comparison to primary operative treatment. Patients with a metaphyseal bone defect of more than 3 cm had significantly lower CS results. Degenerative changes of the teres minor muscle also had a significant negative influence on clinical results. Score results decreased with increasing number of previous operations. There were no significant difference in between patients classified as Boileau type I and II (category 1) compared to types III and IV (category 2). RSA significantly improved the clinical result. A metaphyseal bone defect and preoperative degeneration of the teres minor showed to be negative prognostic factors. Primary operative treatment and the number of previous operations also negatively influenced the clinical result.

Cardiomyopathy of Friedreich ataxia.

Friedreich's ataxia is a rare hereditary, predominantly neurologically defined multisystem disorder of mitochondrial function. Although the gene defect has been identified, the precise pathophysiology of the deficient mitochondrial protein, frataxin, is unknown. Besides the characteristic features of spinocerebellar ataxia the heart may also be affected, and patients may experience a hypertrophic cardiomyopathy eventually progressing toward heart failure and death. So far, research focused on the neurological aspects and little attention has been paid to better characterize and understand the cardiac involvement in Friedreich's ataxia. For that, a better understanding of longitudinal progression, cardiac complications and long-term cardiac outcome is warranted. In addition, the clinician should be familiar with the therapeutic option in Friedreich cardiomyopathy. This review discusses important clinical and diagnostic features of the cardiomyopathy in Friedreich's ataxia and potential therapeutic developments.

Cross-sectional baseline analysis of electrocardiography in a large cohort of patients with untreated Fabry disease.

BACKGROUND: Morphology and function of Fabry cardiomyopathy has been previously studied by echocardiography and cardiac magnetic resonance (CMR). However, the value of electrocardiography (ECG) in relation to these two techniques remains largely unknown. METHODS: One hundred fifty genetically confirmed Fabry patients were investigated using a comprehensive clinical workup comprising 12-lead ECG, echocardiography, and CMR. RESULTS: ECG parameters at rest [PR, P wave, QT, QTc, QT dispersion and time interval from the peak to the end of the T wave (Tpeak to Tend)] were normal in the entire cohort and did not distinguish between males and females or stages of cardiomyopathy. A significant positive correlation was found between left ventricular (LV) mass on CMR and both the QRS duration and the LV Sokolow index, with the highest values in male patients with an advanced cardiomyopathy stage. No prediction of late enhancement on CMR (a sign for replacement fibrosis) was possible by a single ECG parameter. However, the absence of ST or T alterations (in 37 of 38 patients) specifically excluded late enhancement on CMR. CONCLUSION: Our data in a large cohort of Fabry patients, including all cardiomyopathy stages, show, in contrast to former assumptions, that ECG parameters are not suitable to stage Fabry cardiomoypathy. Most ECG parameters were normal in the complete cohort. However, the absence of ST or T alterations seems to almost exclude late enhancement on CMR in these patients.

Lateralized reverse shoulder arthroplasty maintains rotational function of the remaining rotator cuff.

BACKGROUND: Humeral rotation often remains compromised after nonlateralized reverse shoulder arthroplasty (RSA). Reduced rotational moment arms and muscle slackening have been identified as possible reasons for this impairment. Although several clinical studies suggest lateralized RSA may increase rotation, it is unclear whether this is attributable to preservation of rotational moment arms and muscle pretension of the remaining rotator cuff. QUESTIONS/PURPOSES: The lateralized RSA was analyzed to determine whether (1) the rotational moment arms and (2) the origin-to-insertion distances of the teres minor and subscapularis can be preserved, and (3) their flexion and abduction moment arms are decreased. METHODS: Lateralized RSA using an 8-mm resin block under the glenosphere was performed on seven cadaveric shoulder specimens. Preimplantation and postimplantation CT scans were obtained to create three-dimensional shoulder surface models. Using these models, function-specific moment arms and origin-to-insertion distances of three segments of the subscapularis and teres minor muscles were calculated. RESULTS: The rotational moment arms remained unchanged for the middle and caudal subscapularis and teres minor segments in all tested positions (subscapularis, -16.1 mm versus -15.8 mm; teres minor, 15.9 mm versus 15.3 mm). The origin-to-insertion distances increased or remained unchanged in any muscle segment apart from the distal subscapularis segment at 0° abduction (139 mm versus 145 mm). The subscapularis and teres minor had increased flexion moment arms in abduction angles smaller than 60° (subscapularis, 2.7 mm versus 8.3 mm; teres minor, -6.6 mm versus 0.8 mm). Abduction moment arms decreased for all segments (subscapularis, 4 mm versus -11 mm; teres minor, -3.6 mm versus -19 mm). CONCLUSIONS: After lateralized RSA, the subscapularis and teres minor maintained their length and rotational moment arms, their flexion forces were increased, and abduction capability decreased. CLINICAL RELEVANCE: Our findings could explain clinically improved rotation in lateralized RSA in comparison to nonlateralized RSA.

3D-Analysis of the Proximal Humeral Anatomy Before and After Stemless Shoulder Arthroplasty-A Prospective Case Series Study.

BACKGROUND: Stemless shoulder arthroplasty (SSA) is used to anatomically reconstruct proximal humerus geometry and preserve proximal humerus bone stock. The current literature lacks 3D-analysis of pre- and postoperative proximal humeral anatomy after SSA. The aim of this study was to prospectively analyze the humeral head anatomy using a computer-assisted topography mapping technique after SSA in relation to the preoperative status and the contralateral (not affected) side. METHODS: Twenty-nine patients (mean age: 63.5 ± 11.7 years) affected by primary shoulder osteoarthritis and treated with SSA were included. Preoperative and postoperative CT scans of the affected and contralateral sites were analyzed regarding joint geometry. Clinical outcome was assessed by Constant and Disabilities of the Arm, Shoulder and Hand (DASH) score shortly before and one year after surgery. RESULTS: Clinical outcome improved significantly. No correlation between clinical outcome and the evaluated anatomical parameters was found. There was a significant decrease of the humeral head height (p < 0.01) and radius (p = 0.03) in the preoperative versus the postoperative joint geometry. The comparison to the contralateral site showed also a significant decrease of the humeral head height (p < 0.01). All other parameters showed no significant differences. CONCLUSION: Proximal humeral anatomy can be almost anatomically reconstructed by SSA. Solely the humeral head height differs significantly to the preoperative as well as contralateral morphology.

Long-term effects of enzyme replacement therapy on fabry cardiomyopathy: evidence for a better outcome with early treatment.

BACKGROUND: Enzyme replacement therapy with recombinant alpha-galactosidase A reduces left ventricular hypertrophy and improves regional myocardial function in patients with Fabry disease during short-term treatment. Whether enzyme replacement therapy is effective in all stages of Fabry cardiomyopathy during long-term follow-up is unknown. METHODS AND RESULTS: We studied 32 Fabry patients over a period of 3 years regarding disease progression and clinical outcome under enzyme replacement therapy. Regional myocardial fibrosis was assessed by magnetic resonance imaging late-enhancement technique. Echocardiographic myocardial mass was calculated with the Devereux formula, and myocardial function was quantified by ultrasonic strain-rate imaging. In addition, exercise capacity was measured by bicycle stress test. All measurements were repeated at yearly intervals. At baseline, 9 patients demonstrated at least 2 fibrotic left ventricular segments (severe myocardial fibrosis), 11 had 1 left ventricular segment affected (mild fibrosis), and 12 were without fibrosis. In patients without fibrosis, enzyme replacement therapy resulted in a significant reduction in left ventricular mass (238+/-42 g at baseline, 202+/-46 g at 3 years; P for trend <0.001), an improvement in myocardial function (systolic radial strain rate, 2.3+/-0.4 and 2.9+/-0.6 seconds(-1), respectively; P for trend=0.045), and a higher exercise capacity obtained by bicycle stress exercise (106+/-14 and 122+/-26 W, respectively; P for trend=0.014). In contrast, patients with mild or severe fibrosis showed a minor reduction in left ventricular hypertrophy and no improvement in myocardial function or exercise capacity. CONCLUSIONS: These data suggest that treatment of Fabry cardiomyopathy with recombinant alpha-galactosidase A should best be started before myocardial fibrosis has developed to achieve long-term improvement in myocardial morphology and function and exercise capacity.

Impact of myocardial fibrosis in patients with symptomatic severe aortic stenosis.

BACKGROUND: In this prospective follow-up study, the effect of myocardial fibrosis on myocardial performance in symptomatic severe aortic stenosis was investigated, and the impact of fibrosis on clinical outcome after aortic valve replacement (AVR) was estimated. METHODS AND RESULTS: Fifty-eight consecutive patients with isolated symptomatic severe aortic stenosis underwent extensive baseline characterization before AVR. Standard and tissue Doppler echocardiography and cardiac magnetic resonance imaging (late-enhancement imaging for replacement fibrosis) were performed at baseline and 9 months after AVR. Endomyocardial biopsies were obtained intraoperatively to determine the degree of myocardial fibrosis. Patients were analyzed according to the severity of interstitial fibrosis in cardiac biopsies (severe, n=21; mild, n=15; none, n=22). The extent of histologically determined cardiac fibrosis at baseline correlated closely with New York Heart Association functional class and markers of longitudinal systolic function (all P<0.001) but not global ejection fraction or aortic valve area. Nine months after AVR, the degree of late enhancement remained unchanged, implying that AVR failed to reduce the degree of replacement fibrosis. Patients with no fibrosis experienced a marked improvement in New York Heart Association class from 2.8+/-0.4 to 1.4+/-0.5 (P<0.001). Only parameters of longitudinal systolic function predicted this functional improvement. Four patients with severe fibrosis died during follow-up, but no patient from the other groups died. CONCLUSIONS: Myocardial fibrosis is an important morphological substrate of postoperative clinical outcome in patients with severe aortic stenosis and was not reversible after AVR over the 9 months of follow-up examined in this study. Because markers of longitudinal systolic function appear to indicate sensitively both the severity of myocardial fibrosis and the clinical outcome, they may prove valuable for preoperative risk assessment in patients with aortic stenosis.

Degenerative changes of the deltoid muscle have impact on clinical outcome after reversed total shoulder arthroplasty.

INTRODUCTION: Despite a high complication rate, subjective and objective results of reversed shoulder arthroplasty for severe rotator cuff lesions associated with osteoarthritis, fracture sequelae, or revision of hemiarthroplasty are favorable. However, whether the changes in biomechanics of the joint may lead to structural changes in the remaining rotator cuff and the deltoid muscle, and may thereby alter the clinical result, has rarely been described. This study investigates the context between postoperative fatty infiltration of the remaining rotator cuff and the deltoid muscle, and the clinical outcome after reversed shoulder arthroplasty. METHODS: Twenty-three patients with an average age of 73.1 +/- 5.6 years were evaluated at an average of 26 +/- 16.8 months. Evaluation included assessment of Constant Score, disabilities of the arm, shoulder and hand score, radiographic evaluation with measurement of the humeral lengthening and medialization of the center of rotation, and magnetic resonance imaging or computed tomography to classify changes in the rotator cuff and the deltoid muscle. Results There was a significant correlation between fatty infiltration of the deltoid muscle and the clinical score results. Patients with a longer follow-up showed a higher amount of degenerative changes of the deltoid than patients with a shorter follow-up. Degenerative changes of the rotator cuff showed no significant correlation to clinical results. The amount of arm lengthening, medialization of the center of rotation, and scapula notching showed no correlation to clinical results or degenerative changes of the deltoid and the rotator cuff. CONCLUSIONS: These data show that degeneration of the deltoid muscle is of impact for clinical outcome. Although other factors like disuse or pain as a reason for muscular changes cannot be fully excluded, this degeneration might occur after time due to biomechanical changes after reversed arthroplasty. However, prospective studies with longer follow-up periods and repetitive assessment of muscle quality are necessary to further support these results.

Non-invasive determination of pressure recovery by cardiac MRI and echocardiography in patients with severe aortic stenosis: short and long-term outcome prediction.

OBJECTIVE: To assess the influence of pressure recovery (PR)-corrected haemodynamic parameters on outcome in patients with aortic stenosis. METHODS: Aortic stenosis severity parameters were corrected for PR (increase in static pressure due to decreasing dynamic pressure), assessed using transthoracic echocardiography (TTE) or cardiac magnetic resonance imaging (CMR), in patients with aortic stenosis. PR, indexed PR (iPR) and energy loss index (ELI) were determined. Factors that predicted all-cause mortality, and 9-month or 10-year New York Heart Association classification ≥2 were assessed using Cox proportional hazards regression. RESULTS: A total of 25 patients, aged 68 ± 10 years, were included. PR was 17 ± 6 mmHg using CMR, and CMR correlated with TTE measurements. PR correction using CMR data reduced the AS-severity classification in 12-20% of patients, and correction using TTE data reduced the AS-severity classification in 16% of patients. Age (Wald 4.774) was a statistically significant predictor of all-cause mortality; effective orifice area (Wald 3.753) and ELI (Wald 3.772) almost reached significance. CONCLUSIONS: PR determination may result in significant reclassification of aortic stenosis severity and may hold value in predicting all-cause mortality.

Tibiofemoral contact areas and pressures in six high flexion knees.

The tibiofemoral articulating interfaces of six high flexion knee designs were examined using a standard testing protocol developed by Harris et al. [J Biomech 32:951-958 (1999)] to investigate the polyethylene insert contact areas and pressures. A load of 3600 N was applied for 10 s at 0, 30, 60, 90, 110, 135 and 155 degrees of flexion. Contact areas and pressures at the femoral-polyethylene insert interface were measured with a I-scan 4000 system. Up to 110 degrees of flexion, the VANGUARD RP HI-FLEX showed the highest contact area and lowest pressure. At the deep flexion angles, contact area decreased and contact pressure increased significantly in all knees. The NexGen series showed a constant contact area throughout the various flexion angles. In general, all high flexion knees could result in almost point contact in an extremely high range of motion.

Functional differences of left ventricular hypertrophy induced by either arterial hypertension or aortic valve stenosis.

The aim of this study was to reveal functional differences of left ventricular (LV) hypertrophy induced by either aortic stenosis (AS) or arterial hypertension (AH) assessed by strain-rate imaging. Twenty patients with AS and 19 patients with AH were enrolled. In the 2 groups, coronary artery disease was ruled out invasively. All subjects underwent echocardiographic studies, including strain-rate imaging studies of LV long- and short-axis function. Eight patients underwent follow-up examinations after aortic valve replacement, and 20 healthy volunteers served as a control group. LV end-diastolic posterior wall thickness was not different between the 2 patient groups (12.7 +/- 2.5 mm in AS vs 12.8 +/- 1.6 mm in AH) but was significantly increased compared with the control group (8.5 +/- 1.1 mm). The LV ejection fraction was within normal limits in all groups but significantly lower in the patient groups (54 +/- 9% in AS, 55 +/- 6% in AH) compared with the control group (66 +/- 3%). Radial and longitudinal systolic strain rates were depressed in patients with AS compared with those with AH and controls (radial 1.6 +/- 0.6 vs 2.6 +/- 0.6 and 3.8 +/- 0.6 s(-1), respectively, p <0.005). After valve replacement, longitudinal strain rate remained unchanged, but radial strain rate gradually increased (1.6 +/- 0.6 vs 2.1 +/- 0.8 s(-1), p = NS). In parallel, the ejection fraction gradually improved and LV hypertrophy gradually diminished. In conclusion, despite the same degree of LV wall thickness, AS and AH have different impacts on the rate of LV deformation.

Value of low-dose dobutamine stress echocardiography on defining true severe low gradient aortic stenosis in patients with preserved left ventricular ejection fraction.

Low-dose dobutamine stress echocardiography (DSE) is a valuable tool to distinguish true-severe (TS) from pseudo-severe (PS) low gradient aortic valve stenosis (LGAS) in patients with reduced left ventricular ejection fraction (LVEF). However, only scanty studies reported the clinical utility of DSE in differentiating TS-LGAS patients with preserved LVEF. We investigated the clinical utility of DSE in LGAS patients with preserved LVEF and the echocardiographic determinants suggestive of TS-LGAS. 130 consecutive LGAS patients [indexed aortic valve area (AVA) ≤ 0.6cm2/m2 and mean trans-aortic pressure gradient (PGmean) < 40mmHg] with preserved (≥ 50%, n = 63) and reduced (< 50%, n = 67) LVEF were included. DSE defined TS-LGAS (projected AVA ≤ 1 cm2) in 61.2% patients with reduced LVEF and in 68.3% patients with preserved LVEF. Multivariate logistic regression analysis showed that baseline AVA was an independent determinant of TS-LGAS both in LVEF ≥ 50% (OR 0.45, P = 0.004) and LVEF < 50% groups (OR 0.55, P = 0.005). Reduced septal and lateral mitral annular plane systolic excursion (MAPSE, OR 0.72 and 0.75, P = 0.013 and 0.016) and septal TDI-s´ were significantly associated with TS-LGAS in patients with LVEF ≥ 50%. Higher systolic pulmonary artery pressure (SPAP, OR 1.43, P = 0.045) was associated with TS-LGAS in patients with LVEF < 50%. DSE is useful to define TS-LGAS also in patients with preserved LVEF. Lower baseline AVA values are linked with TS-LGAS in both patients with reduced and preserved LVEF. Reduced MAPSE and septal TDI-s´ are suggestive of TS-LGAS in patients with preserved LVEF, while higher SPAP is associated with TS-LGAS in patients with reduced LVEF.

Extent of size, shape and systolic variability of the left ventricular outflow tract in aortic stenosis determined by phase-contrast MRI.

PURPOSE: Left ventricular outflow tract (LVOT) dimensions are important for calculation of aortic valve areas and planning of valve repair. Mostly, LVOT areas are calculated from echocardiographic longitudinal measurements with the assumption of a round shape. Here, orthogonal phase contrast (PC) MRI with dynamic assessment of LVOT was compared to standard longitudinal cine MRI and 2D echocardiography. METHODS: In 19 patients with aortic stenosis (5 female; 69±10years), LVOT areas were determined on orthogonal PC images, either by planimetry (Aplan) or by two-diameter measurement (Aellip). Data were analyzed in early, middle and late systole (t1/t2/t3). Additionally, standard diameter-based calculation (A3CV) of LVOT on longitudinal three-chamber view (3CV) MRI images and 2D echocardiography was performed. RESULTS: Calculated PC LVOT areas strongly correlated to planimetry (r=0.95; p<0.001) with almost identical areas (Aplan 5.1±1.1cm2 vs. Aellip 5.3±1.0cm2). In PC changes of LVOT-eccentricity during systole were most pronounced in late systole (t1 vs. t3plan -7.4±18%). Cine 3CV calculation resulted in lower LVOT areas compared to Aplan (A3CV 3.7±0.9cm2; p<0.001), yet correlating to Aplan (r=0.66; p=0.002). 3CV LVOT areas correlated to echocardiography (r=0.56; p=0.014). CONCLUSIONS: Calculated LVOT areas seem to be sufficient for daily routine. Compared to the orthogonal view, standard long-axis 3CV underestimates the LVOT size and overestimates the systolic reduction of LVOT-size. Systolic changes are most pronounced in late systole.