Clinical implications of pulmonary regurgitation in healthy individuals: detection by cross sectional pulsed Doppler echocardiography

Assessment of right ventricular function by isovolumic acceleration of pulmonary and tricuspid annulus in surgically repaired tetralogy of Fallot

Assessment of right ventricular (RV) function is quite important in patients with surgically corrected tetralogy of Fallot (TOF). However, quantitative assessment of RV function remains challenging, mainly because of the complex RV geometry. This prospective study investigated isovolumic acceleration (IVA), a parameter of myocardial systolic function not influenced by either preload or afterload, using tissue Doppler imaging. We evaluated IVA measured on pulmonary annulus (PA-IVA) and tricuspid annulus (TA-IVA), because we considered that PA-IVA and TA-IVA correspond with systolic function of the RV outflow tract (RVOT) and RV basal function, respectively. Thirty-nine patients with surgically repaired TOF (TOF group) and 40 age-matched healthy children (control group) were enrolled in this study. No significant difference was seen between TA-IVA (2.5 ± 0.8 m/s2) and PA-IVA (2.4 ± 0.8 m/s2) in the control group. In the TOF group, PA-IVA (1.0 ± 0.5 m/s2) was significantly lower than TA-IVA (1.3 ± 0.6 m/s2, p < 0.05). Both TA-IVA and PA-IVA were significantly lower in the TOF group than in the control group (p < 0.05 each). We concluded that PA-IVA offers a useful index to assess RVOT function in TOF patients. J. Med. Invest. 67 : 145-150, February, 2020.

Pulmonic Valve Disease: Review of Pathology and Current Treatment Options

PURPOSE OF REVIEW

Our review is intended to provide readers with an overview of disease processes involving the pulmonic valve, highlighting recent outcome studies and guideline-based recommendations; with focus on the two most common interventions for treating pulmonic valve disease, balloon pulmonary valvuloplasty and pulmonic valve replacement.

RECENT FINDINGS

The main long-term sequelae of balloon pulmonary valvuloplasty, the gold standard treatment for pulmonic stenosis, remain pulmonic regurgitation and valvular restenosis. The balloon:annulus ratio is a major contributor to both, with high ratios resulting in greater degrees of regurgitation, and small ratios increasing risk for restenosis. Recent studies suggest that a ratio of approximately 1.2 may provide the most optimal results. Pulmonic valve replacement is currently the procedure of choice for patients with severe pulmonic regurgitation and hemodynamic sequelae or symptoms, yet it remains uncertain how it impacts long-term survival. Transcatheter pulmonic valve replacement is a rapidly evolving field and recent outcome studies suggest short and mid-term results at least equivalent to surgery. The Melody valve® was FDA approved for failing pulmonary surgical conduits in 2010 and for failing bioprosthetic surgical pulmonic valves in 2017 and has been extensively studied, whereas the Sapien XT valve®, offering larger diameters, was approved for failing pulmonary conduits in 2016 and has been less extensively studied. Patients with pulmonic valve disease deserve lifelong surveillance for complications. Transcatheter pulmonic valve replacement is a novel and attractive therapeutic option, but is currently only FDA approved for patients with failing pulmonary conduits or dysfunctional surgical bioprosthetic valves. New advances will undoubtedly increase the utilization of this rapidly expanding technology.

Impact of Elevated End-Diastolic Pulmonary Regurgitation Gradient on Worse Clinical Outcomes in Hospitalized Patients With Heart Failure

The echo Doppler end-diastolic pulmonary regurgitation (EDPR) gradient correlates well with catheter-derived pulmonary artery diastolic pressure. An elevated EDPR gradient is associated with worse clinical outcomes in patients with stable coronary artery disease. However, the prognostic significance of EDPR gradient in patients with heart failure (HF) is unclear. The aim of the present study was to investigate the prognostic impact of EDPR gradient in HF. We retrospectively examined 751 consecutive hospitalized patients with acute HF. Those with acute coronary syndrome or in-hospital death and those without accessible EDPR gradient data at discharge were excluded. Finally, 265 patients were examined and divided into 2 groups according to EDPR gradient (cutoff 9 mm Hg). Adverse events were defined as worsening HF and death. Patients with elevated EDPR gradient had higher B-type natriuretic peptide, lower age, and lower left ventricular ejection fraction at discharge than those with nonelevated EDPR gradient. During a median follow-up of 429 days, elevated EDPR gradient was independently associated with adverse events (hazard ratio 2.34, 95% CI 1.44 to 3.78, p <0.001) after adjustment for confounders. In conclusion, echo Doppler EDPR gradient might be a noninvasive predictor of clinical outcomes in hospitalized patients with HF.

Changes in speckle tracking echocardiography measures of ventricular function after percutaneous implantation of the Edwards SAPIEN transcatheter heart valve in the pulmonary position

BACKGROUND

Patients with free pulmonary regurgitation or mixed pulmonary stenosis and regurgitation and severely dilated right ventricles (RV) show little improvement in ventricular function after pulmonary valve replacement when assessed by traditional echocardiographic markers. We evaluated changes in right and left ventricular (LV) function using speckle tracking echocardiography in patients after SAPIEN transcatheter pulmonary valve (TPV) placement.

METHODS

Echocardiograms were evaluated at baseline, discharge, 1 and 6 months after TPV placement in 24 patients from 4 centers. Speckle tracking measures of function included peak longitudinal strain, strain rate, and early diastolic strain rate. RV fractional area change, tricuspid annular plane systolic excursion, and left ventricular LV ejection fraction were assessed. Routine Doppler and tissue Doppler velocities were measured.

RESULTS

At baseline, all patients demonstrated moderate to severe pulmonary regurgitation; this improved following TPV placement. No significant changes were detected in conventional measures of RV or LV function at 6 months. RV longitudinal strain (-16.9% vs. -19.6%, P < 0.01), strain rate (-0.87 s(-1) vs. -1.16 s(-1) , P = 0.01), and LV longitudinal strain (-16.2% vs. -18.2%, P = 0.01) improved between baseline and 6 month follow-up. RV early diastolic strain rate, LV longitudinal strain rate and early diastolic strain rate showed no change.

CONCLUSION

Improvements in RV longitudinal strain, strain rate, and LV longitudinal strain are seen at 6 months post-TPV. Diastolic function does not appear to change at 6 months. Speckle tracking echocardiography may be more sensitive than traditional measures in detecting changes in systolic function after TPV implantation.

Early echocardiographic changes after percutaneous implantation of the Edwards SAPIEN transcatheter heart valve in the pulmonary position

OBJECTIVES

To evaluate echocardiographic changes after SAPIEN valve implantation in the pulmonary position.

BACKGROUND

The feasibility of the SAPIEN transcatheter pulmonary valve (TPV) has recently been demonstrated. We evaluated changes in pulmonary valve function and the right ventricle after SAPIEN TPV placement.

METHODS

We evaluated echocardiograms at baseline, discharge, 1 and 6 months after TPV placement in 33 patients from 4 centers. Pulmonary insufficiency severity was graded 0-4. TPV peak and mean gradients were measured. Right ventricular (RV) size and function were quantified using routine measures derived from color, spectral, and tissue Doppler indices and two-dimensional echocardiography.

RESULTS

At baseline, 94% patients demonstrated pulmonary insufficiency grade 2-4. This decreased to 12% patients at 6 months (P < 0.01). TPV peak (P < 0.01) and mean gradient (P < 0.01) decreased. RV end-diastolic area indexed to body surface area (BSA) (P < 0.01), Tricuspid regurgitation (TR) gradient (P < 0.01), and the ratio of TR jet area to BSA (P < 0.01) decreased. Tricuspid inflow peak E:A, tissue Doppler imaging (TDI): septal E' and A', TDI: tricuspid A' improved between baseline and discharge, but trended back to baseline by 6-month follow-up. Tricuspid valve annulus z-score, RV area change, tricuspid annular plane systolic excursion (TAPSE), RV dP/dt, tricuspid E:E', and TDI: tricuspid annulus E' showed no change.

CONCLUSION

Improvements in pulmonary insufficiency and stenosis, RV size, and TR gradient and severity are seen after SAPIEN TPV placement. Selected indices of RV diastolic function improve immediately after TPV implantation, but return to baseline by 6 months. RV systolic function is unchanged.

Long-term outcome of direct neopulmonary artery reconstruction during the arterial switch procedure

BACKGROUND

Neopulmonary stenosis at anastomosis site is one of the most frequent complications after the arterial switch procedure for transposition of the great arteries. The surgical technique is a crucial factor associated with the frequency of stenotic complications. We present the outcomes of direct neopulmonary anastomosis during the arterial switch procedure in patients with simple transposition. This research was to assess the efficacy of this surgical technique based on the incidence of postprocedural supravalvular neopulmonary stenosis (SVPS).

METHODS

Among 545 patients operated on in our department between 1992 and 2009, the 346 consecutive survivors who had undergone simple transposition in the first month of life were included in this analysis. Switch procedures were performed with direct neopulmonary artery anastomosis in 318 patients (92%); in the remaining 28 (8%), the risk of coronary artery compression required the use of a pericardial patch for pulmonary reconstruction.

RESULTS

Neopulmonary stenosis occurred in 9 patients (2.6%): 5 had undergone direct neopulmonary reconstruction, and 4 had been treated with a patch. Balloon angioplasty of SVPS was performed twice in 1 patient. No patients required reoperation to treat neopulmonary stenosis. In multivariate analysis (logistic regression), patch reconstruction (odds ratio, 27.5; p=0.001) and nonfacing commissures (odds ratio, 11.1; p=0.004) were correlated significantly with the incidence of SVPS.

CONCLUSIONS

Direct neopulmonary artery anastomosis during arterial switch is an interesting alternative to patch reconstructions and ensures a good postoperative result with low rates of complications and SVPS.

Echocardiographic characteristics and causal mechanism of physiologic mitral regurgitation in young normal subjects

BACKGROUND

It has become evident that mitral regurgitation (MR) is not uncommon in healthy subjects, and Doppler color flow mapping is a technique that imparts important information relevant to its detection.

HYPOTHESIS

Using transthoracic echocardiography, this study evaluated the mechanism of physiologic MR in young normal subjects using transthoracic echocardiography.

METHODS

The study population consisted of 48 young normal subjects (mean 21 +/- 5 years) with MR (physiologic MR group), 40 age-matched young normal subjects (mean 20 +/- 5 years) without MR (control group), 45 patients (mean 41 +/- 15 years) with mitral valve prolapse with MR (MVP group), and 27 patients (mean 59 +/- 13 years) with ruptured chordae tendineae (rupture group).

RESULTS

Men were predominant in the rupture group, whereas there were no significant gender differences in the other three groups. Left ventricular end-diastolic dimension and left atrial systolic dimension were slightly smaller in the physiologic MR group than in the control group, but were significantly smaller than those in the MVP and rupture groups. The ratio of the maximum anteroposterior diameter to the maximum transverse diameter on chest radiography and the ratio of the short- to long-axis diameter of the left ventricular cavity at end diastole, determined from two-dimensional short-axis echocardiogram, were significantly lower in the physiologic MR group than in the other three groups. Mitral regurgitation occurred more frequently at the posteromedial commissural site in the physiologic MR and MVP groups, whereas there was no preference for location in the rupture group. Early systolic MR was often observed in the physiologic MR group, whereas pansystolic MR was common in the MVP and rupture groups.

CONCLUSION

As a causal mechanism for physiologic MR detected in young normal subjects, "flattening" of the thorax during growth may cause morphologic abnormalities of the left atrial and ventricular cavities, resulting in spatial imbalance of the mitral complex and resulting in malcoaptation of the valve.

Pulmonary regurgitation end-diastolic gradient is a Doppler marker of cardiac status: data from the Heart and Soul Study

BACKGROUND

Echocardiograms routinely sample pulmonary regurgitation signals from which it is possible to measure end diastolic gradients; these correlate with pulmonary artery diastolic pressures.

METHODS

We performed echocardiograms in 741 ambulatory adults with coronary artery disease who were recruited for the Heart and Soul Study. We compared indicators of cardiac status among individuals with normal (0-5.0 mm Hg) and elevated (> 5.0 mm Hg) end diastolic pulmonary regurgitation (EDPR) gradients.

RESULTS

Of the 481 participants with measurable EDPR gradients, 21% had elevated EDPR gradients (> 5.0 mm Hg). EDPR gradients > 5.0 mm Hg were associated with higher New York Heart Association functional class (P = .002), higher brain natriuretic peptide (P = .002), fewer metabolic equivalents achieved on treadmill testing (P < 0.001), and higher left ventricular mass (P < 0.001). The EDPR gradient > 5.0 mm Hg had a sensitivity of 25% (95% confidence interval 20-30%) and a specificity of 86% (80-91%) for detecting at least one of the following: systolic dysfunction, diastolic dysfunction, or abnormal wall motion score. The EDPR gradient > 5.0 mm HG was statistically equivalent to the tricuspid regurgitation (TR) gradient > 30 mm Hg in terms of diagnostic value (area under the receiver operating characteristic curve equaled 0.58 for each test). The EDPR gradient increased the yield of pulmonary artery pressures from 61% (TR gradient alone) to 84% (P < .0001).

CONCLUSION

The EDPR gradient provides valuable information independent of the TR gradient in evaluating pulmonary artery pressures and cardiac dysfunction.

Echocardiographical characteristics of healthy young subjects with physiological mitral regurgitation

We aimed to analyse the echocardiographical characteristics of healthy subjects and determine the causal mechanism of the development of physiological mitral regurgitation (PMR). A total of 130 healthy subjects were divided into two groups according to whether or not PMR was detected. There were no statistical differences between the two groups in terms of the mean values of the systolic and diastolic left ventricular internal diameters and the left atrial diameter. The mean values of the length and thickness of the anterior mitral valve (AMV) and the mitral annular diameter (MAD) from subjects in group 1 (with PMR) were statistically different from those of group 2 (without PMR). In conclusion, the AMV was slightly longer and thicker and the MAD was smaller in subjects with PMR than in subjects without PMR. The changes observed in the AMV and the mitral annulus may play a causal role in the development of PMR.

Pressure half-time predicts hemodynamically significant pulmonary regurgitation in adult patients with repaired tetralogy of fallot

Pulmonary regurgitation (PR) is associated with adverse outcomes late after tetralogy of Fallot repair. Accurate assessment of PR in these patients is, therefore, fundamental to their clinical treatment; however, accurate ultrasound markers of severity are as yet poorly defined. This is a prospective study of 34 adult patients with repaired tetralogy of Fallot. Cardiac magnetic resonance imaging was used to assess the PR fraction and its hemodynamic significance on the right ventricular volumes. Regurgitant fractions >/= 20% were associated with significant increases in right ventricular end-diastolic volumes. Echocardiographic continuous wave Doppler profiles of the PR jet were used to calculate pressure half-time. Pulmonary pressure half-time < 100 milliseconds was found to be a good indicator of hemodynamically significant regurgitation. This measure is highly reproducible and easily accessible.

Long-term invasive and noninvasive results of percutaneous balloon pulmonary valvuloplasty in children, adolescents, and adults

BACKGROUND

Short-term and mid-term results of percutaneous balloon pulmonary valvuloplasty (BPV) are well known. However, data documenting long-term effectiveness of BPV are scarce.

METHODS AND RESULTS

The long-term results of 62 patients were assessed by catheterization and Doppler echocardiography 1 to 10 years (mean 6.4 +/- 3.4) after BPV. Mean age of the patients was 13.5 +/- 10.5 years (range 9 months to 44 years). Twenty patients were 16 years of age or older. Right ventricular peak systolic pressure was systemic or suprasystemic in 72% of patients. A double-balloon technique was used in 29 patients. The balloon-to-pulmonary valve diameter ratio was 1.4 +/- 0.38 (range 1 to 1.8). Total systolic transpulmonary pressure gradient in excess of 50 mm Hg in all patients before BPV decreased from 98 +/- 40 to 32 +/- 23 immediately after BPV and to 19 +/- 9 mm Hg at follow-up (P <.001). Infundibular gradient increased from 8 +/- 10 to 14 +/- 24 mm Hg after BPV and fell to 1 +/- 4 mm Hg at follow-up (P <.01). In 16 patients it was >/=20 mm Hg and virtually disappeared spontaneously in all at follow-up. The valvar gradient fell from 93 +/- 39 to 19 +/- 11 (P <.001) and was 18 +/- 9 mm Hg at follow-up. It remained unchanged in 3 patients (range 36 to 45 mm Hg). In 3 (4.8%) other patients, a new gradient >35 mm Hg developed that was >/=50 mm Hg in all 3. Among 5 patients having dysplastic valves, 3 had a gradient >35 mm Hg. There were no predictors of a gradient >35 mm Hg at long-term follow-up by univariate or multivariate Cox proportional hazards analysis. Mild to moderate pulmonary regurgitation was present in 39% of patients. On electrocardiography, right ventricular hypertrophy decreased significantly in 90% of patients.

CONCLUSIONS

BPV as a treatment of typical pulmonic valve stenosis produces excellent long-term results. Restenosis is rare (4.8%) and occurs more frequently in patients with dysplastic valves. There is a constant spontaneous regression of associated infundibular obstruction.

Right-sided valvular regurgitation in normal children determined by combined colour-coded and continuous-wave Doppler echocardiography

Using Doppler echocardiography, the prevalence of tricuspid and pulmonary valve regurgitation was determined prospectively in 173 normal children, aged 8.3 +/- 2.7 (range 5-14) years. Pulmonary regurgitation was defined as a red-yellow or mosaic coloured regurgitant flow, continuing to end-diastole with continuous-wave Doppler. It was found in 84% of the children. Tricuspid regurgitation was defined as a blue-green or mosaic coloured regurgitant flow from the tricuspid valve into the right atrium lasting > 0.5 systole, as determined by continuous-wave Doppler. Tricuspid regurgitation was present in only 8% of the children. Tricuspid regurgitation flow of very short duration, considered to be due to valve closure, was found in 75%. No effect of age, presence of a vibratory innocent heart murmur or gender on the prevalence of right-sided valvular regurgitation could be demonstrated. All regurgitations were haemodynamically insignificant. Thus right-sided valvular regurgitation in normal schoolchildren is a normal physiological finding with relatively high prevalence. In the absence of functional reasons for these regurgitations and in the absence of structural pulmonary or tricuspid valve disease, these signals should be considered physiological in order to avoid iatrogenic heart disease.

An anatomical study of the healthy human heart by echocardiography with special reference to physiological valvular regurgitation

110 healthy subjects (45 men and 65 women ranging in age between 24 and 60 years) were studied by 2-dimensional echocardiography. In each subject the diameters of the cardiac chambers, the thickness of the intraventricular septum and posterior wall of the left ventricle in diastole, as well as the diameters and circumferences of the aortic and mitral rings were measured. Moreover, in each subject color doppler echocardiography was performed. Pulmonary valve regurgitation was observed in 47 subjects (42.7%). This finding was not correlated in a statistically significant manner to either age, sex, body weight, or height. The incidence of pulmonary regurgitation, however, tended to decrease with age. In 37 subjects (33.6%), tricuspid regurgitation was detected without any correlation to the above parameters. In 11 cases (10%), mitral regurgitation was observed; its correlation to age was statistically significant (p < 0.05). Aortic regurgitation was noted in 9 (8.2%) cases; its incidence was directly correlated to age (p < 0.01). The observed regurgitations were defined as "physiological" and precise characteristics were chosen so as to distinguish such "physiological" from "pathological" regurgitations.

Physiologic multivalvular regurgitation during pregnancy: a longitudinal Doppler echocardiographic study

Valvular function, assessed by Doppler technique, has not been extensively investigated during normal pregnancy. To prospectively study this feature, 18 normal pregnant women were followed during their pregnancies and puerperium, with serial clinical and pulsed-continuous Doppler echocardiographic examinations. In four gestational periods and the puerperium, we analysed: (a) ventricular and atrial dimensions, as well as valve annular diameters; (b) prevalence and characteristics of trivial valvular regurgitations. During pregnancy, slight but significant increases of the four cardiac chamber dimensions and valve annular diameters were observed, except for the aortic ring. The prevalence of physiologic valvular regurgitation in early pregnancy (mitral, 0%; tricuspid, 38.9%; pulmonary, 22.2%; aortic, 0%), was similar to a control group of 18 healthy non-pregnant women. As pregnancy evolved, there was a progressive and significant increase of multivalvular regurgitation, maximal at full-term (mitral, 27.8%; tricuspid, 94.4%; pulmonary, 94.4%, P < 0.05 vs. early pregnancy). Aortic regurgitation was not detected in any stage of pregnancy. In the puerperium, mitral regurgitation resolved, but tricuspid and pulmonary regurgitation were still significantly prevalent (83.3% and 66.7%, respectively, P < 0.05 vs. early pregnancy). It is concluded that physiologic multivalvular regurgitation is frequent in pregnancy, mainly involving right-sided valves in late gestational periods, occasionally persisting in the early puerperium. Chamber enlargement, valve annular dilatation, and increased prevalence of trivial valve regurgitation are time-related events during normal pregnancy, resulting from a reversible cardiac remodeling process induced by physiologic volume overload. These aspects should be considered for a correct interpretation of Doppler echocardiographic findings in pregnant women with suspected heart disease.

Pulmonary artery diastolic pressure: a simultaneous Doppler echocardiography and catheterization study

Pulmonary hypertension is an important determinant of the clinical presentation of and surgical approach to patients with heart disease. To confirm the utility of continuous wave Doppler echocardiography in assessing the pulmonary artery diastolic pressure in patients with pulmonary regurgitation, 51 patients representing the wide hemodynamic spectrum of pulmonary artery pressure underwent simultaneous determination of pulmonary artery diastolic pressure by continuous wave Doppler echocardiography and cardiac catheterization. Pulmonary artery diastolic pressure was estimated from the Doppler recordings by the end-diastolic pressure gradient obtained by the modified Bernoulli equation plus the estimated right atrial pressure. A correlation was observed (r = 0.935, SEE = 7.4 mmHg) between Doppler and catheterization pulmonary artery diastolic pressure. In addition, comparison between the mean diastolic pressure gradient across the pulmonary valve by Doppler and pulmonary artery diastolic pressure at catheterization yielded a high correlation (r = 0.947, SEE = 5.1 mmHg). These data demonstrate that continuous wave Doppler echocardiography is a useful noninvasive technique for evaluating the pulmonary artery diastolic pressure in patients with pulmonary regurgitation.

The prevalence of valvular regurgitation in children with structurally normal hearts: a color Doppler echocardiographic study

To determine the prevalence of valvular regurgitation in children (from birth to 14 years old) with structurally normal hearts, the records of 1360 consecutive patients referred for echocardiographic and Doppler examination were analyzed. A total of 461 (33.9%) patients were found to have structurally normal hearts. Flow patterns across the four valves were examined by pulsed, continuous-wave, and color Doppler imaging techniques. Regurgitation was detected in 124 (26.9%). Pulmonic regurgitation was most commonly found and was detected in 101 (21.9%) patients, tricuspid regurgitation in 29 (6.3%), and mitral regurgitation in 11 (2.4%). Aortic regurgitation was not found. Regurgitation of one valve occurred in 106 (23.0%) patients and of two valves in 18 (3.9%) patients. No patient had regurgitation of more than two valves. The prevalence of pulmonic regurgitation increased significantly with age (p less than 0.0001), whereas the prevalence of mitral, tricuspid, and bivalvular regurgitation did not change with age. Valvular regurgitation was trivial or mild in 87% of patients. Thus mild valvular regurgitation is commonly found in children with structurally normal hearts.

The Graham Steell murmur: eponymous serendipity?

On 7 March 1888 Dr Graham Steell addressed the Manchester Medical Society in the premises of the Literary and Philosophical Society in George Street, Manchester. He chose as his subject 'The auscultatory signs of mitral obstruction and regurgitation', and later that year published two papers on the same theme in the Manchester Medical Chronicle. In one he wrote: 'I wish to plead for the admission among the recognised auscultatory signs of disease of a murmur due to pulmonary regurgitation, such regurgitation occurring independently of disease or deformity of the valves, and as the result of long-continued excess of blood pressure in the pulmonary artery'. His observations were later confirmed by pathological correlation, and more cases were reported, notably by Paul White. The early diastolic murmur of pulmonary incompetence caused by pulmonary hypertension is now associated eponymously with Dr Graham Steell. We review the life and work of this physician and conclude that the original source of the observation, subsequently validated by modern techniques, was probably George Balfour of Edinburgh, and that Graham Steell was fortunate to have this physical sign attributed to him.

Prospective Doppler echocardiographic evaluation of pulmonary artery diastolic pressure in the medical intensive care unit

To test the hypothesis that the noninvasive evaluation of pulmonary regurgitation can provide accurate estimates of pulmonary artery (PA) diastolic pressures and PA wedge pressures, Doppler echocardiographic studies were performed immediately before bedside PA catheterization in 29 medical intensive care unit patients. The characteristic color flow Doppler signal of pulmonary regurgitation was detected in 19 (66%) patients. In 17 of the 29 patients (59%), the gradient between the right ventricle and PA at end-diastole could be calculated from the pulsed-wave Doppler signal of pulmonary regurgitation using the simplified Bernoulli equation. Right atrial pressure was then estimated by examination of the jugular venous pulse or by electronic transduction of the pressure signal from a previously placed central venous catheter. A noninvasive estimate of PA diastolic pressure was made by adding the clinical estimate of right atrial pressure to the end-diastolic pressure gradient across the pulmonary valve. Pulmonary artery catheterization was then performed and stripchart recordings were interpreted by a physician who was unaware of the noninvasively-estimated PA diastolic pressure. The PA diastolic pressure estimated by Doppler echocardiography correlated closely with that found at catheterization (r = 0.94, mean absolute difference 3.3 mm Hg). The noninvasive estimate of PA diastolic pressure also correlated with the PA wedge pressure (r = 0.87, mean absolute difference 3.8 mm Hg). Therefore, in 59% of medical intensive care unit patients, Doppler echocardiographic evaluation of pulmonary regurgitation allowed accurate noninvasive estimation of PA diastolic pressure.

Pulsed and continuous wave Doppler echocardiographic assessment of valvular regurgitation in normal subjects

To assess the prevalence and flow characteristics of valvular regurgitation detected by Doppler echocardiography in normal subjects, pulsed and continuous wave Doppler studies were performed in 100 adult volunteers without evidence of heart disease. Evidence of valvular regurgitation was present in 73% of subjects. There were 46 subjects with regurgitation of one valve, 24 with regurgitation of two valves and 3 with regurgitation of three valves. Right-sided regurgitation was significantly more common than was left-sided regurgitation (81 versus 22 valves, p less than 0.01). Regurgitant flow was never detected farther than 1 cm from the valve by pulsed Doppler study. Tricuspid regurgitation was detected in 50 subjects and was characterized by a holosystolic velocity signal; a complete spectral envelope was recorded in 32 subjects. The peak velocity of the regurgitant jet for this group was 1.7 to 2.3 m/s (mean 2.0 +/- 0.2). Thirty-one subjects were found to have pulmonary regurgitation with a peak velocity of 1.2 to 1.9 m/s (mean 1.5 +/- 0.2); no subject demonstrated regurgitant flow in early diastole. There were 21 subjects with mitral regurgitation; continuous wave Doppler signals were always of low intensity with a poorly defined spectral envelope and an absence of high velocities. Peak velocities ranged from 1.1 to 4.4 m/s (mean 2.3 +/- 0.9) and in 19 subjects were less than 3.5 m/s. The mean age of subjects with mitral regurgitation was significantly higher than that of subjects without mitral regurgitation (p = 0.01). Aortic regurgitation was detected in only one subject. This study provides further evidence that valvular regurgitation is frequently detected by Doppler echocardiography in normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Diastolic atrioventricular valve closure and regurgitation following atrial contraction: their relation to timing of atrial contraction

Some authors have proposed that atrial contraction per se is able to close the atrioventricular (AV) valves. To determine whether tight closure of the AV valves can be accomplished solely by atrial contraction, the existence of diastolic regurgitation following atrial contraction and its relation to the PQ interval were examined in 13 patients with AV block (2 of the first degree, 4 of the second degree, and 7 of the third degree), using pulsed Doppler echocardiography, which allowed noninvasive estimation of valvular regurgitation in the physiological state. Diastolic mitral and tricuspid regurgitations were detected in the left and right atria near the respective AV valves in all 13 patients despite different degrees of AV block, while these valves were observed to be in apparently closed position during regurgitation on the two-dimensional and M-mode echocardiograms. The duration of regurgitant signals was prolonged with an increase in the PQ interval in the electrocardiogram, but it became short again as the P wave approached the preceding rapid filling wave. These results suggest that atrial contraction may initiate the closure of the AV valves but is not capable of closing the valves tightly, and atrial contraction with long PQ interval may contribute little to augmentation of cardiac output in patients with AV block.