右心室快速临时起搏同时经皮球囊扩张术治疗婴幼儿主动脉瓣狭窄

目的探讨经皮球囊主动脉瓣成形术更加安全地治疗婴幼儿先天性主动脉瓣狭窄的方法和疗效。方法从股动脉途径对婴幼儿先天性主动脉瓣狭窄患者行经皮球囊主动脉瓣成形术。术中扩瓣同时应用右室快速临时起搏使左心室和主动脉收缩压下降,从而使扩张瓣膜的球囊在左室流出道位置稳定,减少球囊的移动和对瓣膜的损伤。结果 1岁2个月和3岁的男性患者2例,体重分别7Kg、16 Kg,球囊/瓣环直径比分别0.83和0.8。术后即刻主动脉收缩峰压跨瓣压差分别从80 mm Hg和90 mm Hg下降至20 mm Hg和18 mm Hg。随访2个月～1年,超声心动图检测主动脉瓣跨瓣压差分别38 mm Hg、43 mm Hg,主动脉瓣返流无明显增加。结论经皮球囊主动脉瓣成形术是治疗婴幼儿先天性主动脉瓣狭窄行之有效的方法。扩瓣同时右室快速临时起搏可保持球囊稳定,减少并发症。     

经导管主动脉瓣置换术治疗白塞病合并重度主动脉瓣反流一例

目前,白塞病合并重度主动脉瓣反流的主要治疗方式为外科主动脉瓣置换术,但术后瓣周漏、瓣膜撕脱等严重并发症的发生率高。该文报道1例合并白塞病的重度主动脉瓣反流患者,接受经导管主动脉瓣置换术治疗后症状改善明显。随访2年,超声心动图提示人工瓣膜流速、跨瓣压差处于正常范围,无明显瓣周漏;心脏增强CT扫描未见瓣叶增厚、撕脱情况,短期临床效果满意。     

主动脉瓣四叶瓣畸形合并主动脉瓣病变的外科处理

目的 探讨主动脉瓣四叶瓣畸形对主动脉瓣功能的影响及其外科治疗.方法 2000年1月至2013年1月,我院通过经胸超声心动图和术中病理诊断主动脉瓣四叶瓣畸形13例.其中4例主动脉瓣的功能基本正常,9例合并主动脉瓣病变：重度关闭不全7例,重度关闭不全伴狭窄2例,合并二尖瓣中度关闭不全2例,三尖瓣中重度关闭不全1例.结果 13例患者中4例主动脉瓣功能正常者,继续随访中.9例合并主动脉瓣病变者,均行主动脉瓣置换术,同期行二尖瓣成形术2例、三尖瓣成形术1例.围术期无严重并发症及早期死亡,均康复出院.术后平均随访（6.34±5.17）年,心彩超提示主动脉瓣功能良好,无远期死亡.结论 主动脉瓣四叶瓣畸形是一种少见的先天性畸形,超声心动图有助于早期诊断.主动脉瓣功能正常时,可以随访;当合并主动脉瓣功能障碍时,应及时行主动脉瓣置换或修复,手术后可获得良好的远期效果.     

38例二尖瓣成形术临床分析

目的总结38例二尖瓣成形术的临床经验.方法实施二尖瓣成形术38例,其中,后叶矩形切除9例,"双孔法"13例,后叶腱索转移3例,后叶矩形切除 "双孔法"2例,后叶腱索转移 "双孔法"3例,前、后交界环缩2例,单纯放人工瓣环4例,瓣叶穿孔修补2例.本组35例植入人工瓣环.结果术后经食管超声心动图(TEE)检查二尖瓣反流消失或微量反流32例,少量反流6例.1例术后第一天发生瓣膜撕裂,行二尖瓣替换术后痊愈.1例术后第九天因消化道出血,继发肾功能衰竭死亡.36例术后早期超声复查,二尖瓣舒张期流速0～1.9m/s,平均(1.23±0.39)m/s.跨瓣压差0～14.4mmHg,平均(6.61±3.56)mmHg.36例随访2～70个月,心功能Ⅰ级31例,Ⅱ级5例.结论对于二尖瓣关闭不全的患者,术中准确判断二尖瓣的病变,采用相应的成形技术,可以取得良好的早、中期治疗效果.     

二尖瓣成形术在婴幼儿先天性心脏病中的应用

目的：总结二尖瓣成形术在婴幼儿先天性心脏病（先心病）中的应用.方法：自2007年10月至2012年10月,108例二尖瓣关闭不全（不包括完全性或部分性房室通道）婴幼儿行二尖瓣成形手术,所有婴幼儿中有3例（2.7％）行再次二尖瓣成形术.术中根据瓣膜病变情况选择合适的成形方法,包括二尖瓣瓣环环缩、Wooler瓣环成形术、瓣裂修补、乳头肌缩短技术及复合技术.对所有患者均行临床和超声心动图检查评估二尖瓣功能.结果：全组婴幼儿无死亡病例,所有婴幼儿复查超声心动图提示：二尖瓣残留少量反流23例（21.3％）,中度反流12例（11.1％）,重度反流3例（2.7％）,3例重度反流患几分别于术后2年、2年9个月及4年行再次手术,再次手术后1例无反流,2例少量反流.结论：二尖瓣成形术是婴幼儿先心病中二尖瓣关闭不全手术的首选术式,均能取得良好的治疗效果     

风湿性主动脉瓣病变行主动脉瓣成形术34例临床分析

目的 总结34例风湿性主动脉瓣病变行主动脉瓣成形手术的经验.方法 2005年6月至2010年9月,共34例风湿性主动脉瓣患者行主动脉瓣成形术,其中男性20例,女性14例,年龄22～70（43.1±14.8）岁.成形方法：主动脉瓣交界切开6例,交界切开并纤维增厚结节切除6例,单纯纤维增厚结节切除2例,瓣膜心包延伸术2例,瓣叶小体修复术4例,瓣叶交界折叠6例,瓣叶交界折叠并夹闭环缩术6例,瓣膜楔形切除术2例.结果 无死亡病例,并发症发生率5.9%,其中低心排1例、急性肾功能不全1例.26例无反流,8例轻度反流.结论 风湿性主动脉瓣病变掌握好成形的指征,选择恰当的成形方式,可取得良好的治疗效果.     

二尖瓣位机械瓣梗阻的彩色多普勒评价

目的评价彩色多普勒超声在诊断二尖瓣位机械瓣(单叶碟瓣)梗阻的价值。方法对比二尖瓣位机械瓣梗阻12例的彩色多普勒超声结果与手术所见。结果左心长轴切面和心尖四腔切面可较清晰地显示二尖瓣位机械瓣梗阻患者的瓣叶活动显著受限,瓣叶开放角度平均10°(0°-25°),彩色血流束呈单束或双束狭窄的边缘血流束,无瓣周漏及中度以上的瓣关闭不全,最大跨瓣血流速度及压差无显著改变:术中见12例瓣叶均被“卡”在近关闭状态位,开放角度小于300°,瓣周纤维肉芽组织增生伴血栓形成,瓣口狭小(0-0．5mm),其中4例瓣口及瓣周完全被血栓块“封堵”。结论彩色多普勒超声心动图显示机械瓣梗阻特征为瓣叶开放角度和幅度显著减小,瓣口呈边缘性狭窄血流束,与手术所见一致,但瓣口血流速度及压差指数等特异改变在彩色多普勒超声心动图不明显;虽然彩色多普勒超声心动图对异常增生组织和血栓的显示不清晰,但仍不失为诊断二尖瓣位机械瓣梗阻的简便有效的手段。     

超声心动图在主动脉瓣狭窄经导管主动脉瓣植入术中的应用价值

目的探讨超声心动图在主动脉瓣狭窄患者经导管主动脉瓣植入术中的作用。方法3例重度主动脉瓣瓣膜狭窄患者接受经导管主动脉瓣人工瓣膜植入术。使用PhilipS iE33型彩色多普勒超声诊断仪,配备经胸探头S5—1和经食道探头S7—2,X7—2t。超声观察内容包括明确主动脉瓣膜病变范围和程度,测量主动脉瓣环前后径,人工瓣膜植入术后瓣膜功能等。结果3例患者经导管主动脉瓣植入术均取得了成功,人工瓣膜位置稳定,常规超声心动图3例患者术前经胸超声心动图与术中经食管超声心动图诊断相符,跨瓣压差较术前明显下降,主动脉瓣瓣上流速明显下降,瓣周漏瞬时反流量平均约1．2mL。结论经导管主动脉瓣人工瓣膜植入术在治疗严重主动脉瓣瓣膜狭窄中方法可行,效果良好;超声心动图在这项工作中具有重要的辅助作用。     

主动脉左室通道术后随访研究

目的:评价主动脉左室通道外科治疗结果,探讨超声心动图在主动脉左室通道的外科治疗后随访中的临床应用价值.方法:随访我院1999-03至2008-08手术治疗的主动脉左室通道8例患者,均行常规二维超声心动图检查,5例患者同时行三维超声心动图检查.结果:二维超声心动图检杳显示未行主动脉瓣替换者主动脉瓣无反流1例,轻度主动脉瓣反流1例,轻～中度主动脉瓣反流2例,主动脉左室通道再通1例;行主动脉瓣替换者机械瓣功能正常2例,瓣周漏1例.三维超声心动图以多种视角观察主动脉瓣及临近组织,进一步补充诊断.结论:主动脉左室通道外科治疗后应长期随访观察,超声心动图在随访中发挥重要的作用,实时三维超声心动图在二维超声心动图基础上,能显示主动脉瓣及其临近结构的空间立体结构,进一步协助诊断.     

单纯超声引导经皮球囊主动脉瓣成形术治疗先天性主动脉瓣狭窄的远期结果分析

目的 分析单纯超声引导经皮球囊主动脉瓣成形术(PBAV)治疗先天性主动脉瓣狭窄(CAS)的远期结果。方法 回顾性分析2016年1月至2018年12月收治的采用单纯超声引导PBAV治疗的CAS患者13例。收集PBAV手术资料、超声心动图检查结果。采集患者手术前后主动脉瓣环直径、球囊直径与球囊瓣环直径比(BAR)、主动脉瓣反流、左心室短轴缩短率(LVFS)、左心室舒张末期内径(LVEDD)、主动脉瓣血流速度(AV)、平均跨瓣压差(MTPG)、峰值跨瓣压差(PTPG)、主动脉瓣口面积(AVA)、左心室射血分数(LVEF),并进行比较。同时观察患者术后并发症发生情况。结果 BAR为0.92±0.06。术后患者的LVEDD为(51.6±6.5)mm,小于术前的(65.2±5.9)mm;术后AV为(3.7±0.8)m/s,低于术前的(4.8±0.6)m/s;术后即刻MTPG为(33.8±13.9)mm Hg(1 mmHg=0.133 kPa),低于术前的(54.5±13.8)mmHg;术后即刻PTPG为(37.2±9.4)mm Hg,低于术前的(82.7±19.9)mmHg;术后AVA为(2.0±...     

Comparison of aortic valve gradient during exercise after aortic valve reconstruction

PURPOSE: Aortic valve preservation is a promising alternative to conventional composite replacement of aortic valve and ascending aorta. This approach may have a physiologic benefit compared with valve replacement similar to that seen in mitral valve reconstruction. We investigated aortic valve gradients at rest and during exercise in patients who had undergone valve-preserving aortic replacement and compared them with composite replacement of valve and aorta. METHODS: Four groups were studied: nine patients underwent composite valve replacement (group A: valve diameter, 23 to 27 mm), eight patients underwent remodeling of the aortic root (group B), and another nine patients had reimplantation of the aortic valve (group C). Healthy volunteers were studied as a control group (group D). Using continuous-wave Doppler echocardiography, all patients were examined on a bicycle ergometer for aortic valve gradients (0 to 75 W). RESULTS: There were no differences among the groups with respect to age, body surface, left ventricular end-diastolic diameter, fractional shortening, or left ventricular mass. Maximum resting gradients were significantly elevated in group A compared with groups B, C, and D (group A: 21.3 +/- 7.1 mm Hg; group B: 9.0 +/- 4.5 mm Hg; group C: 8.6 +/- 3.7 mm Hg; group D: 4.9 +/- 1.6 mm Hg; p < 0.05). At 75 W, group A exhibited significantly higher gradients than all other groups (group A: 31.3 +/- 7.5 mm Hg; group B: 13.9 +/- 6.6 mm Hg; group C: 12.8 +/- 3.5 mm Hg; group D: 9. 2 +/- 1.9 mm Hg; p < 0.05). There was no significant difference among the other groups. Both valve-preserving groups had only insignificantly higher gradients than the control group. CONCLUSION: Our data strongly support the suggestion that preserving the aortic valve restores nearly normal hemodynamic function of the aortic valve. Long-term observations will have to prove the clinical relevance of restoring physiologic aortic valve hemodynamics.     

Simplified method for estimating true aortic valve mean gradient from simultaneous left ventricular and peripheral arterial pressure recordings

Estimation of the aortic valve gradient by simultaneous recording of left ventricular and peripheral arterial pressures is subject to error due to delay and modulation of the arterial pressure contour as it propagates from the ascending aorta. This error can be corrected by averaging the mean gradients derived from unaltered and temporally aligned simultaneous left ventricular-peripheral arterial pressure tracings. In 26 patients with aortic stenosis and simultaneous recordings of ascending aortic and femoral arterial pressure we compared this method with a simplified approach in which the peripheral arterial pressure is partially aligned by advancing it against the left ventricular pressure by 50% of the time delay of the simultaneously recorded upstrokes. Gradients measured this way predicted the true aortic valve gradients (left ventricular-ascending aortic) with a mean difference of +1.1 mm Hg (range = +10 to -5 mm Hg). We recommend use of this simplified method of correction because it predicts true aortic valve gradient equally well as the averaging technique (r = 0.977 vs. 0.979) and requires half the time and effort.     

The influence of sizing on the dynamic function of the free-hand implanted porcine aortic homograft: an in vitro study.

BACKGROUND AND AIMS OF THE STUDY: The influence of sizing on the function of a porcine aortic valve after its implantation using the free-hand technique in the subcoronary position was investigated. METHODS: Dynamic function and leaflet configuration of the valve (n = 16) were first analyzed in its natural aortic root in a left heart simulator at 120/80 mmHg pressure and 4 l/min cardiac output. The valve was then implanted in the recipient porcine aortic root and re-studied. Three groups were investigated: group I (n = 4) comprised of 1-2 mm smaller donor aortic valve than the recipient; group II (n = 8) 3-4 mm smaller; and group III (n = 4) 5-7 mm smaller. Orifice area (OA), systolic and diastolic configurations of the leaflets, pattern and timing of leaflet opening and closure, commissural movement, pressure gradient and valvular regurgitation were analyzed. RESULTS: In the intact donor aortic root, average expansion of the aorta at the commissures, for a pressure change from 0 to 80 mmHg, was about 42%. This was reduced significantly in all assemblies. Group I showed a 34% reduction in OA, and excessive leaflet bending; there was no aortic insufficiency (AI) or pressure gradient across the valve. In group III there was a lesser reduction in OA and reduced leaflet bending, but two of four valves had AI. In group II, the reduction in OA was only 13%, there was less leaflet bending, and no AI. CONCLUSIONS: The donor valve 3-4 mm smaller than the recipient seems an optimal match. The current practice of using the same size donor as recipient may be responsible for excessive leaflet bending and may be implicated in early deterioration of the homograft.     

Validity of an early postoperative baseline Doppler recording after aortic valve replacement

In 131 patients undergoing aortic valve replacement (53 bioprostheses, 78 mechanical), the pressure decrease across the prosthesis was recorded with Doppler ultrasound at a baseline study early postoperatively (mean 11 +/- 5 days) and compared with a repeat measurement 3 to 5 months later. At baseline the hemodynamic state was markedly different, with increased heart rate (89 +/- 14 vs. 74 +/- 13 beats/min, p less than 0.001) and decreased left ventricular ejection time index (367 +/- 21 vs 390 +/- 22, p less than 0.001). A minor and clinically insignificant decrease in pressure decrease with time was found. The 95% confidence interval for the difference was 0.2 to 3.0 and 0.2 to 1.7 mm Hg for the peak and the mean pressure decrease, respectively. The change in pressure decrease was statistically significant for bioprostheses (mean 16 +/- 5 vs 14 +/- 4 mm Hg, p less than 0.01) and smaller (less than or equal to 23 mm) valves (mean 17 +/- 4 vs 15 +/- 4 mm Hg, p less than 0.01), whereas no significant changes were found for mechanical valves or valves of a larger size. The change in mean pressure decrease from baseline to the second examination was within +/- 5 mm Hg for 82% of patients. It is concluded that despite a different hemodynamic state in the early postoperative period, the pressure decrease across aortic valve prostheses obtained at this time can be used as a reference for later comparison.     

Estimation of mechanical stresses on closed cusps of porcine bioprosthetic valves: effects of stiffening, focal calcium and focal thinning

The magnitude and distribution of mechanical stresses acting on the closed cusps of porcine bioprosthetic valves (PBVs) were estimated using a finite element model. The effects of leaflet stiffening, focal calcium and focal thinning on leaflet stresses were determined. In a normal closed PBV leaflet, stresses increased as pressure was increased. At a pressure of 80 mm Hg, the maximal normal principal stresses were 11 g/mm2 near the center of the leaflet and increased to 19 g/mm2 at a pressure of 160 mm Hg. These observations suggest that the closed valve in the mitral position would experience higher mechanical stresses than the closed valve in the aortic position. Tissue stiffening increased stresses throughout the leaflet and introduced a site of stress concentration near the center of the leaflet. At a pressure of 80 mm Hg, the maximal principal normal stress increased 55% when the leaflet was stiff in comparison to the normal leaflet. Focal calcium and focal thinning caused marked gradients of stress between the sites of calcium or thinning and the immediate surrounding tissue. The magnitude of these stress gradients increased with increasing pressure. These sites of mechanical stress concentration or stress gradients appear to be compatible with sites of leaflet calcification or disruption. Such stresses may contribute to spontaneous degeneration of PBVs.     

Dobutamine stress echocardiography and left ventricular mass changes of mechanical aortic valve replacement in four years follow-up

AIM: The aim of this study was to investigate the differences in cardiac response to stress according to the size of the prosthetic valve in patients who underwent aortic valve replacement (AVR) and to evaluate the relationship between the size of the prosthetic valve and cardiac recovery-remodeling after the operation. METHODS: Thirty patients who had undergone AVR (12 patients) or double valve replacement (18 patients) underwent dobutamine-stress echocardiography 4.2 years after the operation to evaluate response to stress . They were divided into 2 groups according to valve prosthesis size. The small-size AVR group (group 1, n=17) had prosthetic aortic valves 21 pounds mm; the large-size AVR group (group 2, n=13) had valves >21 mm. Response to stress and preoperative and postoperative echocardiographic findings were compared. Pulsed and continuous-wave Doppler studies were performed at rest and at the end of each stage. Peak and mean aortic gradients, left ventricular diastolic and systolic functions were measured for each group. RESULTS: Dobutamine stress increased heart rate and blood pressure in both groups. Peak pressure gradient across the aortic valve prostheses was 42.1 mm Hg in group 1 and 20.9 mm Hg in group 2 (P<0.05) at rest. After dobutamine infusion, the peak pressure gradient across the aortic valve prostheses increased to 85.1 mm Hg in group 1 and 54 mm Hg in group 2 (P<0.05). Isovolumetric relaxation time returned to normal in both groups following dobutamine infusion; this decrease was significant only in group 1. Patients achieved a decrease in left atrium and left ventricular diameters and volumes, as evidence of remodeling following AVR. Left ventricular mass index (LVMI) decreased from 127.6+/-47.6 to 98.1+/-36.9 and from 159.9+/-16.1 to 125.3+/-10.1 in groups 1 and 2, respectively, but this decline was not statistically significant. CONCLUSIONS: Smaller valves have higher gradients and this significant difference increases under stress. Significant improvement in echocardiographic diameters, cardiac filling volumes and LVMI reflects the benefit of the operation. Cardiac remodeling is independent of valve size, although high transprosthetic gradients occur during stress conditions.     

Validation of a generalized transfer function to noninvasively derive central blood pressure during exercise

Exercise brachial blood pressure (BP) predicts mortality, but because of wave reflection, central (ascending aortic) pressure differs from brachial pressure. Exercise central BP may be clinically important, and a noninvasive means to derive it would be useful. The purpose of this study was to test the validity of a noninvasive technique to derive exercise central BP. Ascending aortic pressure waveforms were recorded using a micromanometer-tipped 6F Millar catheter in 30 patients (56+/-9 years; 21 men) undergoing diagnostic coronary angiography. Simultaneous recordings of the derived central pressure waveform were acquired using servocontrolled radial tonometry at rest and during supine cycling. Pulse wave analysis of the direct and derived pressure signals was performed offline (SphygmoCor 7.01). From rest to exercise, mean arterial pressure and heart rate were increased by 20+/-10 mm Hg and 15+/-7 bpm, respectively, and central systolic BP ranged from 77 to 229 mm Hg. There was good agreement and high correlation between invasive and noninvasive techniques with a mean difference (+/-SD) for central systolic BP of -1.3+/-3.2 mm Hg at rest and -4.7+/-3.3 mm Hg at peak exercise (for both r=0.995; P<0.001). Conversely, systolic BP was significantly higher peripherally than centrally at rest (155+/-33 versus 138+/-32 mm Hg; mean difference, -16.3+/-9.4 mm Hg) and during exercise (180+/-34 versus 164+/-33 mm Hg; mean difference, -15.5+/-10.4 mm Hg; for both P<0.001). True myocardial afterload is not reliably estimated by peripheral systolic BP. Radial tonometry and pulse wave analysis is an accurate technique for the noninvasive determination of central BP at rest and during exercise.     

先天性二叶式主动脉瓣畸形所致主动脉瓣狭窄的外科治疗体会

目的总结先天性主动脉瓣二叶式畸形所致的主动脉瓣狭窄手术治疗的经验。方法1995年9月至2010年12月福建医科大学附属协和医院心外科共为46例二叶式主动脉瓣畸形所致主动脉瓣狭窄患者实施了瓣膜置换术。对这些患者的手术效果及其影响因素进行回顾性总结。结果术后随访3个月至12年,死亡1例（为猝死）,1例出现与抗凝有关的脑部并发症;心功能Ⅰ级36例,心功能Ⅱ级9例。术后超声心动图测得主动脉瓣跨瓣压差17～51（29．2±11．5）mmHg。结论主动脉瓣置换术是治疗先天性主动脉瓣二叶式畸形所致主动脉瓣的有效疗法,应尽可能选择有效瓣口面积较大的人造瓣膜,这样可以有效降低术后主动脉跨瓣压差,提高手术安全性和远期疗效。     

Determination of right ventricular pressure in the presence of a ventricular septal defect using continuous wave Doppler ultrasound

Continuous wave Doppler ultrasound was employed in 38 patients with ventricular septal defects, many with associated lesions, to measure the velocity (V) of the shunted blood. Using the modified Bernoulli equation (delta P = 4V2) the pressure difference (delta P) between the ventricles was determined. In 22 patients both right ventricular and either left ventricular or ascending aortic pressure were measured at the time shunt velocity was determined. In another 16 patients these measurements were not obtained simultaneously but in most they were done within 24 hours of each other. In the entire group, measured pressure differences between the ventricles (or aorta and right ventricle) ranged from 0 to 97 mm Hg (mean 52 +/- 24). On the basis of velocity measurements the pressure difference ranged from 7 to 112 mm Hg (mean 51 +/- 24). A close correlation was found between the two methods (r = 0.95, SEE = 7.8 mm Hg). This accuracy was not altered by associated lesions. These findings indicate that by the use of continuous wave Doppler interrogation right ventricular pressure can be accurately measured in the presence of a ventricular septal defect.     

"Overestimation" of catheter gradients by Doppler ultrasound in patients with aortic stenosis: a predictable manifestation of pressure recovery.

OBJECTIVES: This study sought to evaluate whether pressure recovery can cause significant differences between Doppler and catheter gradients in patients with aortic stenosis, and whether these differences can be predicted by Doppler echocardiography. BACKGROUND: Pressure recovery has been shown to be a source of discrepancy between Doppler and catheter gradients across aortic stenoses in vitro. However, the clinical relevance of this phenomenon for the Doppler assessment of aortic stenosis has not been evaluated in patients. METHODS: Twenty-three patients with various degrees of aortic stenosis were studied with Doppler echocardiography and catheter technique within 24 h. Using an equation previously validated in vitro, pressure recovery was estimated from peak transvalvular velocity, aortic valve area and cross-sectional area of the ascending aorta and compared with the observed differences between Doppler and catheter gradients. Doppler gradients were also corrected by subtracting the predicted pressure recovery and then were compared with the observed catheter gradients. RESULTS: Predicted differences between Doppler and catheter gradients due to pressure recovery ranged from 5 to 82 mm Hg (mean +/- SD, 19 +/- 16 mm Hg) and 3 to 54 mm Hg (12 +/- 11 mm Hg) for peak and mean gradients, respectively. They compared well with the observed Doppler-catheter gradient differences, ranging from -5 to 75 mm Hg (18 +/- 18 mm Hg) and -7 to 48 mm Hg (11 +/- 13 mm Hg). Good correlation between predicted pressure recovery and observed gradient differences was found (r = 0.90 and 0.85, respectively). Both the noncorrected and the corrected Doppler gradients correlated well with the catheter gradients (r = 0.93-0.97). However, noncorrected Doppler gradients significantly overestimated the catheter gradients (slopes, 1.36 and 1.25 for peak and mean gradients, respectively), while Doppler gradients corrected for pressure recovery showed good agreement with catheter gradients (slopes, 1.03 and 0.96; standard error of estimate [SEE] 8.1 and 6.9 mm Hg; mean difference +/- SD 0.4 +/- 8.0 mm Hg and 1.1 +/- 6.8 mm Hg for peak and mean gradients, respectively). CONCLUSIONS: Significant pressure recovery can occur in patients with aortic stenosis and can cause discrepancies between Doppler and catheter gradients. However, pressure recovery and the resulting differences between Doppler and catheter measurements may be predicted from Doppler velocity, aortic valve area and size of the ascending aorta.