Diagnosis of constrictive pericarditis by two-dimensional echocardiography: studies in a new experimental model and in patients

A novel model of constrictive pericarditis associated with myocardial fibrosis in rats

An efficient animal model is fundamental for studies on the underlying mechanisms of constrictive pericarditis (CP). A novel CP rat model was established by pericardial injection composing of lipopolysaccharides (LPS) and talcum powder without thoracotomy. Pathological changes were confirmed by histological staining. E-flow Doppler of mitral valve, tissue Doppler E' in the medial mitral annular (E'sep ) and the lateral mitral annular (E'lat ) were measured to assess ventricular filling function. Circumferential, longitudinal, and radial strains (SC, SL and SR) and the respective strain rates (SrC, SrL and SrR) were analyzed in interventricular septum (IVS) and left ventricular free wall (LVFW). Rat cardiac fibroblasts (CFs) were treated with LPS. The activation of transforming growth factor β1 (TGF-β1) was confirmed by Q-PCR and western blot assays. Thickening of pericardium and fibrosis in pericardium and subepicardial myocardium were showed in the model group. Diastolic dysfunction in the CP group was indicated by decreased E'lat and E'lat /E'sep , increased E/E'lat , decreased EFW of SrC and SrL, increased AIVS and decreased E/A of SrC, SrL and SrR. Systolic dysfunction was indicated by decreased SCFW and SLFW in CP rats. The levels of TGF-β1, p-Smad2/3, α-smooth muscle actin (α-SMA), and collagen-I/III (COL-I/III) were increased in the CP group. The increased TGF-β1 that induced by LPS activated and phosphorylated Smad2/3 resulting in the secretion of α-SMA and COL-I/III. This model is of vital importance in studying the pathogenesis of CP.

Systematic review of non-invasive cardiovascular imaging in the diagnosis of constrictive pericarditis

Background

Diagnosis of constrictive pericarditis (CP) can be challenging. It can be nearly impossible to distinguish CP from other causes of right heart failure. Although various imaging modalities help in the diagnosis, no test is definitive. Several reviews have addressed the role of various imaging techniques in the diagnosis of CP but a systematic review has not yet been published.

Objective

Our intention was to study the ability of various non-invasive imaging modalities to diagnose CP in patients with surgically confirmed disease and to apply our findings to develop a clinically useful diagnostic algorithm.

Methods

A PubMed (NLM) search was performed with MeSH term “constrictive pericarditis”. Original articles that investigated the ability of various cardiovascular imaging modalities to noninvasively diagnose surgically confirmed CP were included in our review. Investigations that included any cases without surgical confirmation were excluded.

Results

The PubMed search yielded 3001 results with MeSH term “constrictive pericarditis” (January 8, 2016). We identified (40) studies on CP that matched our inclusion criteria. We summarized our results sorted by individual non-invasive CV imaging modalities – echocardiography, cardiac computed tomography (CT), and magnetic resonance imaging (MRI). Under each imaging modality, we grouped our discussion based on different parameters useful in CP diagnosis.

Conclusions

In conclusion, contemporary diagnosis of CP is based on clinical features and echocardiography. Cardiac MRI is recommended in patients where echocardiography is not diagnostic. Both cardiac MRI and CT can guide surgical planning but we prefer MRI as it provides both structural and functional information.

Constrictive Pericarditis as a Never Ending Story: What's New?

Nowadays, we have a better understanding of the natural history of constrictive pericarditis such as transient constriction. In addition, we have acquired the correct understanding of hemodynamic features that are unique to constrictive pericarditis. This understanding has allowed us to diagnose constrictive pericarditis reliably with Doppler echocardiography and differentiation between constrictive pericarditis and restrictive cardiomyopathy is no longer a clinical challenge. The advent of imaging modalities such as CT or MR is another advance in the diagnosis of constrictive pericarditis. We can accurately measure pericardial thickness and additional information such as the status of coronary artery and the presence of myocardial fibrosis can be obtained. We no longer perform cardiac catheterization for the diagnosis of constrictive pericarditis. However, these advances are useless unless we suspect and undergo work-up for constrictive pericarditis. In constrictive pericarditis, the most important diagnostic tool is clinical suspicion. In a patient with signs and symptoms of increased systemic venous pressure i.e. right sided heart failure, that are disproportionate to pulmonary or left sided heart disease, possibility of constrictive pericarditis should always be included in the differential diagnosis.

Transient constrictive pericarditis: an elusive diagnosis

Constrictive pericarditis (CP) is caused by reduction in the elasticity of the pericardium resulting in impaired diastolic filling of the heart. All types of CP were thought to be irreversible in the past. This led to a belief that all patients with CP should undergo pericardiectomy. However, at present, it is well established that selected patients can be treated without pericardiectomy, leading to the concept of transient CP. Clinical improvement can be spontaneous or accomplished with empirical medical therapy administered for several months. As for chronic form, transient CP may not be recognized due to the difficulty in establishing the diagnosis because of the absence of any single method that is 100% sensitive and specific. It is worth considering the possibility of transient type when constrictive physiology is detected by noninvasive methods because correct diagnosis may prevent the inflamed pericardium from becoming the chronic fibrotic type that can be associated with more serious consequences including pericardiectomy.

Coronary microvascular endothelial function deteriorates late (12 months) after sirolimus-eluting stent implantation

BACKGROUND

Coronary flow velocity reserve (CFVR) may reflect coronary microvascular endothelial function in the absence of significant epicardial coronary artery stenosis. The purpose of this study was to evaluate coronary microvascular endothelial function late (6 and 12 months) after sirolimus-eluting stent (SES) implantation using transthoracic Doppler echocardiography.

METHODS AND RESULTS

A total of 21 lesions from 21 patients with significant left anterior descending artery stenosis who underwent percutaneous coronary intervention (PCI) with SES were enrolled and studied. As a control group, 10 patients who were treated with bare metal stent (BMS) were also studied. CFVR was measured at 6 and 12 months after PCI. Coronary angiography was also performed at 6 and 12 months (SES only) after stenting. Between 6 and 12 months after SES implantation, there was no significant difference in angiographical diameter stenosis. On the other hand, CFVR significantly decreased between 6 and 12 months in the SES group (2.5±0.5 vs. 2.2±0.5, p<0.01), but not in the BMS group (2.3±0.4 vs. 2.5±0.3, p=0.1).

CONCLUSIONS

Coronary microvascular endothelial function may deteriorate between 6 and 12 months after SES implantation.

An unusual cause of severe dyspnea: diastolic dysfunction due to calcific constrictive pericarditis

BACKGROUND

Constrictive pericarditis is a rare cause of dyspnea. This disease shares many signs and symptoms with other causes of cardiac failure as well as gastrointestinal and renal diseases, making it difficult to diagnose.

CASE REPORT

We present a case of a 73-year-old woman who presented to our Emergency Department (ED) in respiratory failure after a recent history of worsening dyspnea. Constrictive pericarditis was strongly suspected on bedside ultrasonography. Computed tomography scan showed extensive pericardial calcifications and large pleural effusions, supporting the diagnoses. The patient was admitted for treatment and evaluation of constrictive pericarditis, but died of complications during cardiac catheterization.

CONCLUSIONS

The etiology and physiology of constrictive pericarditis are reviewed and an ultrasound-centered approach to undifferentiated dyspnea in the ED is discussed.

Differentiation between restrictive cardiomyopathy and constrictive pericarditis by early diastolic doppler myocardial velocity gradient at the posterior wall

BACKGROUND

The differential diagnosis between restrictive cardiomyopathy (RCM) and constrictive pericarditis (CP) is challenging and, despite combined information from different diagnostic tests, surgical exploration is often necessary.

METHODS AND RESULTS

A group of 55 subjects (mean age, 63+/-11 years; 36 men and 19 women) were enrolled in the study; 15 had RCM, 10 had CP, and 30 were age-matched, normal controls. The diagnosis of RCM was supported by a biopsy; in the CP group, the diagnosis was confirmed either surgically or at autopsy. All patients underwent a transthoracic echocardiogram that included the assessment of Doppler myocardial velocity gradient (MVG), as measured from the left ventricular posterior wall during the predetermined phases of the cardiac cycle. MVG was lower (P<0.01) in RCM patients compared with both CP patients and normal controls during ventricular ejection (2. 8+/-1.2 versus 4.4+/-1.0 and 4.7+/-0.8 s(-1), respectively) and rapid ventricular filling (1.9+/-0.8 versus 8.7+/-1.7 and 3.7+/-1.4 s(-1), respectively). Additionally, during isovolumic relaxation, MVG was positive in RCM patients and negative in both CP patients and normal controls (0.7+/-0.4 versus -1.0+/-0.6 and -0.4+/-0.3 s(-1), respectively; P<0.01). During atrial contraction, MVG was similarly low (P<0.01) in both RCM and CP patients compared with normal controls (1.6+/-1.7 and 1.7+/-1.8 versus 3.8+/-0.9 s(-1), respectively).

CONCLUSIONS

Doppler myocardial imaging-derived MVG, as measured from the left ventricular posterior wall in early diastole during both isovolumic relaxation and rapid ventricular filling, allows for the discrimination of RCM from CP.

Constrictive pericarditis

The diagnosis of constrictive pericarditis remains a challenge because its physical findings and hemodynamics mimic restrictive cardiomyopathy. Various diagnostic advances over the years enable us to differentiate between these two conditions. This review begins with a case report of constrictive pericarditis, followed by a brief history and discussions of etiologies. Clinical features, radiologic, electrocardiographic, angiographic findings, and hemodynamics of constrictive pericarditis are reviewed. The echocardiographic findings are detailed and the recent advances in Doppler flow velocity patterns of pulmonary, mitral, tricuspid valves and hepatic veins are reported. Nuclear ventriculograms depict rapid ventricular filling in constrictive pericarditis and differentiate it from restrictive cardiomyopathy. Endomyocardial biopsy helps further in recognizing the various types of restrictive cardiomyopathies. Computed tomography and magnetic resonance imaging delineate abnormal pericardial thickness in constrictive pericarditis. Association of characteristic hemodynamic changes and abnormal pericardial thickness > 3 mm usually confirms the diagnosis of constrictive pericarditis. Effusive and occult varieties of constrictive pericarditis are briefly described. This review concludes with emphasizing the importance of pericardial resection.

Pericardial thickness measured with transesophageal echocardiography: feasibility and potential clinical usefulness

OBJECTIVES

This study assessed the reliability of transesophageal echocardiographic measurements of pericardial thickness and the potential diagnostic usefulness of this technique.

BACKGROUND

Transthoracic echocardiography cannot reliably detect thickened pericardium. The superior resolution achieved with transesophageal echocardiography should allow better pericardial definition.

METHODS

Pericardial thickness measured at 26 locations in 11 patients with constrictive pericarditis who underwent intraoperative transesophageal echocardiography was compared with pericardial thickness measured with electron beam computed tomography. Intraobserver and interobserver variabilities were determined. Pericardial thickness was then measured in 21 normal subjects. With these values as a guide, two observers reviewed 37 transesophageal echocardiographic studies to determine whether echocardiographic measurement of pericardial thickness could be used to distinguish diseased from normal pericardium.

RESULTS

The correlation between echocardiographic and computed tomographic measurements (r > or = 0.95, SE < or = 0.06 mm, p < 0.0001) was excellent. The +/-2 SD limits of agreement were +/-1.0 mm or less for pericardial thickness < 5.5 mm and +/-2.0 mm or less for the entire range of thicknesses. Intraobserver and interobserver agreements were good. Mean normal pericardial thickness was 1.2 +/- 0.8 mm (+/-2 SD) and did not exceed 2.5 mm. Pericardial thickness > or = 3 mm on transesophageal echocardiography was 95% sensitive and 86% specific for the detection of thickened pericardium.

CONCLUSIONS

Measurement of pericardial thickness with transesophageal echocardiography is reproducible and should be a valuable adjunct in assessing constrictive pericarditis.

Differentiation of constrictive pericarditis from restrictive cardiomyopathy: assessment of left ventricular diastolic velocities in longitudinal axis by Doppler tissue imaging

OBJECTIVES

We sought to determine the utility of left ventricular expansion velocities in differentiating constrictive pericarditis from restrictive cardiomyopathy.

BACKGROUND

Several studies have shown that left ventricular diastolic expansion is influenced by the elastic recoil forces of the myocardium. These forces are affected by intrinsic myocardial disease but should be preserved when diastole is impaired as a result of extrinsic causes.

METHODS

Using Doppler tissue imaging, we measured peak early velocity of longitudinal axis expansion (Ea) in 8 patients with constrictive pericarditis, 7 patients with restriction and 15 normal volunteers. Transmitral early (E) and late (A) Doppler flow velocities, left ventricular systolic and diastolic volumes, ejection fraction and mitral annular M-mode displacement were also compared between the groups.

RESULTS

The Ea value was significantly higher in normal subjects (14.5 +/- 4.7 cm/s [mean +/- SD]) and in patients with constriction (14.8 +/- 4.8 cm/s) than in those with restriction (5.1 +/- 1.4 cm/s, p < 0.001 constriction vs. restriction). There was weak correlation between Ea and the extent of annular displacement (r = 0.55, p = 0.004) and the E/A ratio (r = 0.44, p = 0.03). There was no correlation between Ea and E (r = 0.33, p = 0.07) or ejection fraction (r = 0.21, p = 0.26). By multivariate analysis, Ea was the best variable for differentiating constriction from restriction.

CONCLUSIONS

Our study indicates that longitudinal axis expansion velocities are markedly reduced in patients with restrictive cardiomyopathy. The poor correlation found with transvalvular flow velocities suggests that Ea may be relatively preload independent. The measurement of longitudinal axis expansion velocities provides a clinically useful distinction between constrictive pericarditis and restrictive cardiomyopathy and may prove to be valuable in the study of diastolic function.

Preimplantation echo Doppler evaluation of VVI versus DDD pacing

This study was carried out to select before permanent pacemaker implantation patients with complete atrioventricular block (CHB) who would benefit best from DDD pacing, and to determine the optimal atrioventricular delay (AVD) for each of those patients. This was achieved with the aid of Doppler echocardiography. The effect of different AVDs on both the systolic and diastolic function of the normal and failing heart was also delineated in this study.

METHODS

Thirty patients with CHB and normal sinoatrial function were selected, with no age or sex predilection. These patients were categorized into three equal groups: groups A, B, and C with normal left ventricular (LV) systolic and diastolic function, LV diastolic dysfunction, and LV systolic dysfunction, respectively. For each patient, systolic and diastolic function was calculated utilizing echo Doppler during CHB, temporary VDD pacing with different AVDs, and temporary VVI pacing with a rate matching that during VDD mode. Temporary VDD mode of pacing was performed utilizing a temporary bipolar ventricular lead for ventricular pacing and an esophageal lead for atrial sensing to trigger ventricular pacing.

RESULTS

Qualitatively the most obvious change in the pattern of LV filling as AVD is increased in the three groups, is the earlier occurrence of active atrial filling A wave due to progressive approximation of the ECG P wave toward the previous QRS. As the AV interval is increased, the following changes occur: (a) A wave occurs progressively earlier with superimposition onto the early filling E wave resulting in a progressive increase in its velocity (VA), its FVI, and its percent atrial contribution (%AC); (b) the three times diastolic filling time (DFT), mitral valve opening to Q wave (MVO-Q), and closure (Q-MVC) progressively shorten; (c) since DFT decreases, less passive filling occurs early during diastole, thus E.FVI decrease with longer AV intervals; (d) the ratios VE/VA and FVI E/A decrease subsequently to the previous described changes. Compared to CHB, percent ejection fraction (% EF) was not significantly changed during VVI pacing. Percent EF increased significantly during VDD in comparison to VVI pacing modes. Percent EF was highest at optimal AVD and decreased as this AVD increased or decreased. The cardiac output (CO) increment during VDD in comparison to VVI pacing modes differed much among the three groups. In group A, a 10.29% increase in CO was seen when comparing VDD pacing (with optimal AVD) with that of VII one; in group B, this increment was much greater and reached 29.48%; in group C it reached 23.68%.(ABSTRACT TRUNCATED AT 400 WORDS)

Accurate preoperative diagnosis of pericardial constriction using cine computed tomography

OBJECTIVES

The purpose of this study was to determine the accuracy of cine computed tomography in the diagnosis of constrictive pericarditis.

BACKGROUND

Constrictive pericarditis is characterized by abnormalities of both cardiac structure and function. Accurate diagnosis requires detection of both a thickened pericardium and abnormal ventricular diastolic filling. At present, no one diagnostic technique has demonstrated sufficient accuracy in this setting. Cine computed tomography is a relatively new cardiac imaging mode with very high time and spatial resolution that has the potential to accurately diagnose constrictive pericarditis.

METHODS

Twelve consecutive patients were retrospectively identified who had catheterization findings suggestive of constrictive physiology, had undergone a cine computed tomographic examination and had pathologic data that delineated the status of the pericardium. Group 1 (with constrictive pericarditis; n = 5) had surgical confirmation of thickened pericardium and improved clinically after pericardiectomy. Group 2 (no constrictive pericarditis; n = 7) had cardiomyopathy with normal pericardium. Seven normal volunteers (Group 3) were also studied. Cine computed tomograms were obtained for the entire heart (8-mm slices, 17 frames/s, nonionic contrast medium). Pericardial thickness was measured at 10 degrees intervals at three ventricular levels in each subject. The rapidity of diastolic filling was assessed by calculating the percent filling fraction in early diastole.

RESULTS

Pericardial thickness was 10 +/- 2 mm (mean +/- SD) in Group 1, 2 +/- 1 mm in Group 2 and 1 +/- 1 mm in Group 3 (p < 0.05, constrictive pericarditis vs. no constrictive pericarditis). Left ventricular filling fraction was 83 +/- 6% in Group 1, 62 +/- 9% in Group 2 and 44 +/- 5% in Group 3. Right ventricular filling fraction was 93 +/- 5% in Group 1, 62 +/- 14% in Group 2 and 35 +/- 6% in Group 3 (p < 0.05, Group 1 vs. Groups 2 and 3). Both indexes provided a clear-cut distinction between patients with and without constriction.

CONCLUSIONS

Cine computed tomography simultaneously provides both anatomic and physiologic data that allow accurate preoperative diagnosis of pericardial constriction.

The differentiation between restrictive cardiomyopathy and constrictive pericarditis: the impact of the imaging techniques

The differentiation between constrictive pericarditis and restrictive cardiomyopathy remains a difficult problem for clinical cardiologists. Recent advances in imaging techniques and the understanding of diastolic function have created a new diagnostic approach to this problem. In this article we will summarize the recent advances in the understanding of the pathophysiology of both disorders and how this is reflected mainly in the use of flow imaging techniques, such as Doppler echocardiography and radionuclide angiography. Combined with the advances in the radiological imaging of the pericardium by means of computed tomography and magnetic resonance imaging, an integrated approach to the differential diagnostic problem is proposed and an algorithm for clinical use has been designed.

A fatal case of constrictive pericarditis due to a marked, selective pericardial accumulation of amyloid

Distinguishing constrictive pericarditis from restrictive cardiomyopathy, usually due to amyloidosis, is a relatively frequent and difficult diagnostic problem. This report describes, for the first time, a patient with constrictive pericarditis caused by direct, extensive infiltration of the pericardium by amyloid, with only minimal amyloid in the myocardium, and a normal heart weight of 320 g. This patient demonstrates that amyloid may be predominantly deposited in the pericardium and actually cause constrictive pericarditis, as well as simulate its hemodynamic presentation by myocardial deposition. Given a clinical and hemodynamic presentation compatible with either constrictive or restrictive disease, an endomyocardial biopsy or other biopsy revealing amyloidosis does not necessarily rule out pericardial constriction that may be due to amyloid infiltration. The relationship between constrictive pericarditis, seen in this patient, and the other more common manifestations of amyloid heart disease, and the hemodynamic profiles of amyloid cardiomyopathy and constrictive pericarditis are reviewed.

Diagnosis of pericardial abnormalities by 2D-echo: a pathology-echocardiography correlation in 85 patients

A blinded pericardial echocardiography-pathology correlation was performed using 85 pericardiectomy or autopsy patients. All patients had two-dimensional (2D)-echocardiography performed within 6 months of autopsy or surgery. 2D-echocardiography was able to detect pericardial abnormalities in 35% of patients with a pathologic pericardium. Obliterative processes, such as fibrosis after open-heart surgery, were particularly not well detected echocardiographically. A specificity of 90% to detect pericardial abnormalities is reported. Acute fibrin strands, malignancies, and chronic fibrous connective tissue involving the pericardium were recognized as abnormal. Interobserver variability does exist, but overall reporting was similar. Specific 2D-echocardiographic signs of pericardial disease require prospective validation including direct pathologic correlation.

A simplified technique for the production of heart failure in the dog by rapid ventricular pacing

Prolonged rapid ventricular pacing (VP) in dogs produces low output heart failure (HF) characterized by cardiomegaly, ascites, and elevated plasma renin and norepinephrine levels. Commercially available pacemaker generators have a protective circuit that prevents pacing at rapid rates. Previously, investigators have had to use either external temporary pacemakers or customized generators to pace at rates greater than 130 beats per minute (bpm). The authors have developed a simple method to perform rapid VP by gluing magnets on Medtronic VVI generators, which allows programming in a temporary mode to sustain rates up to 400 bpm. Our results using 10 generators in 55 dogs demonstrates that HF is produced in all dogs when VP is maintained at 250 bpm for an average of 28 days. Technical difficulties during our early experience with this technique included magnets becoming unglued, loss of capture, and wound complications requiring generator removal. Thus, our method reuses commercially available generators to rapidly pace the ventricles and induce HF.

The pathophysiology of pericardial disease--contributions derived from echocardiography/Doppler studies in animal models

The use of acute and chronically prepared animal models of pericardial disease free of the confounding influences of other disease processes have greatly accelerated the development of echocardiographic and Doppler diagnostic methods and have allowed the correlation of these noninvasive findings with hemodynamic abnormalities.

Abnormal left ventricular-left atrial posterior wall contour: a new two-dimensional echocardiographic sign in constrictive pericarditis

We measured the angle P formed by the junction of the left ventricular and left atrial posterior walls, and also the distances from the ultrasound transducer to the left ventricular posterior wall and left atrial posterior wall (DV and DA), respectively, in the parasternal long-axis two-dimensional echocardiographic view. We studied 23 normal adults and four patient groups with conditions commonly associated with left atrial dilatation: mitral regurgitation (14), mitral stenosis (16), hypertrophic cardiomyopathy (13), and constrictive pericarditis (7). Statistically significant differences were found between the constrictive pericarditis group and each of the other groups. Angle P was less than 150 degrees in 0 of 23 normal individuals, in 0 of 14 with mitral regurgitation, in 1 of 16 with mitral stenosis, in 0 of 13 with hypertrophic cardiomyopathy, and in five of seven with constrictive pericarditis. DA minus DV exceeded 20 mm in 0 of 23 normal individuals, one of four with mitral regurgitation, in 6 of 16 with mitral stenosis, in 0 of 13 with hypertrophic cardiomyopathy, and in five of seven patients with constrictive pericarditis; We conclude that angle P greater than 150 degrees suggests constrictive pericarditis; DA minus DV greater than 20 mm suggests constrictive pericarditis if mitral stenosis can be excluded.

Differentiation of restrictive cardiomyopathy from pericardial constriction: assessment of diastolic function by radionuclide angiography

Diastolic filling variables were studied in 12 patients with the hemodynamic features of constriction, of whom 5 had restrictive cardiomyopathy, 5 had pericardial constriction and 2 had combined pericardial constriction and restrictive cardiomyopathy. The values were compared with those in 10 normal subjects of comparable age. The filling fractions between 10% and 70% of the diastolic time interval were greater in patients with pericardial constriction than in those with restrictive cardiomyopathy (p less than 0.01 between 20% and 50%, p less than 0.05 at 10%, 60% and 70%), with no overlap. The filling fractions in patients with pericardial constriction were also greater than those in normal subjects between 10% and 60% of the diastolic time interval. The filling fraction was lower in patients with restrictive cardiomyopathy than in normal subjects at 40% of the diastolic time interval (p less than 0.05). The time to peak filling rate in patients with pericardial constriction was shorter (110 +/- 14 ms) than in those with restrictive cardiomyopathy (195 +/- 45 ms, p less than 0.01) or in normal subjects (173 +/- 32 ms, p less than 0.01). The percent of atrial contribution to left ventricular filling was higher in those with restrictive cardiomyopathy (45 +/- 17%) than in those with pericardial constriction (21 +/- 6%, p less than 0.05) or in normal subjects (24 +/- 9%, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis of constrictive pericarditis by pulsed Doppler echocardiography of the hepatic vein

The diagnostic value of hepatic venous flow patterns was evaluated for constrictive pericarditis by pulsed Doppler. A characteristic flow pattern was assumed to be associated with the well-known atrial pressure curve. Thirteen patients with constrictive pericarditis were compared to 13 control subjects and to 25 patients with right ventricular pressure overload including 13 patients with tricuspid regurgitation. The characteristic finding in constrictive pericarditis was a W-wave pattern of flow velocities in the dilated hepatic veins, with abrupt reversal of flow late in systole and diastole before the A wave (100% specificity, 68% sensitivity). This depends, however, on the absence of tricuspid regurgitation (for its systolic component) or fast sinus rhythm (for its diastolic component). Additional diagnostic markers were systolic deceleration time of forward flow (40 to 130 ms) and systolic integral of flow velocities (4.3 to -4.0 cm) (sensitivity and specificity greater than or equal to 92%). In the presence of tricuspid regurgitation, diastolic deceleration time less than 150 ms and diastolic integral of flow velocities less than 6 cm were useful diagnostic signs. If combined, these criteria had 100% sensitivity and specificity for the diagnosis. Thus, pulsed Doppler assessment of flow velocities in the hepatic vein facilitates the diagnosis of constrictive pericarditis in clinical routine, using an auxiliary site with unlimited diagnostic access to the characteristic flow velocity pattern, which reflects right atrial pressure curve and filling abnormalities.

Differentiation of constrictive pericarditis and restrictive cardiomyopathy by Doppler echocardiography

Doppler ultrasound recordings of mitral, tricuspid, aortic, and pulmonary flow velocities, and their variation with respiration, were recorded in 12 patients with a restrictive cardiomyopathy and seven patients with constrictive pericarditis. Twenty healthy adults served as controls. The patients with constrictive pericarditis showed marked changes in left ventricular isovolumic relaxation time and in early mitral and tricuspid flow velocities at the onset of inspiration and expiration. These changes disappeared after pericardiectomy and were not seen in patients with restrictive cardiomyopathy or in normal subjects. The deceleration time of early mitral and tricuspid flow velocity was shorter than normal in both groups, indicating an early cessation of ventricular filling, but only patients with restrictive cardiomyopathy showed a further shortening of the tricuspid deceleration time with inspiration. Diastolic mitral and tricuspid regurgitation was also more common in the patients with restrictive cardiomyopathy. These results suggest that patients with constrictive pericarditis and restrictive cardiomyopathy can be differentiated by comparing respiratory changes in transvalvular flow velocities. In addition, although baseline hemodynamics in the two groups were similar, characteristic changes were seen with respiration that suggest differentiation of these disease states may also be possible from hemodynamic data.

Late results after pericardectomy for constrictive pericarditis via left thoracotomy

Pericardectomy was performed on 28 men and 8 women (mean age 56, range 18-74 years) with diagnosis constrictive pericarditis. The etiology was unknown in 16 cases. Left anterior thoracotomy was employed in all but one case, in which median sternotomy was preferred because of extensive left pleural calcifications. There were three early and 11 late deaths. Actuarial survival at 5 and 10 years was 77% and 64%, respectively. Relief of symptoms was reported by 16 of the 33 patients (49%), who survived the postoperative period. These 16 were among the 22 survivors observed for a median of 8 (range 2-17) years postoperatively. Complete pericardectomy was achieved in all 16 asymptomatic patients, but in only nine of the 17 hospital survivors (53%), with persistent heart failure (p less than 0.01). Pericardial calcifications were significantly less common in the former than in the latter group. Lack of postoperative improvement was related to severe, nonresectable calcifications, and probably in some cases to associated fibrous epicarditis or restrictive myocardial disease. Left thoracotomy permits easier and more complete left ventricular pericardectomy, but is less safe when severe calcifications involve the right ventricle and atrium.

Doppler echocardiographic assessment of the effect of varying atrioventricular delay and pacemaker mode on left ventricular filling

Pulsed Doppler echocardiography was used to study the timing and dynamics of left ventricular filling in 14 patients with permanent dual-chamber programmable pacemakers. Pacemakers were programmed to atrial sensed (VDD) mode and atrial-ventricular sequential paced mode at low (DVI-L) and high (DVI-H) heart rates, and pulsed Doppler recordings of transmitral flow were analyzed at atrioventricular delays of 50 to 300 msec in each mode. There was a significant decrease in the one-third filling fraction in both VDD and DVI-L modes and a significant increase in DVI-H modes with increasing atrioventricular delay. The ratio of early filling area to atrial filling area was significantly lower at longer atrioventricular delays in both VDD and DVI-L modes. The time from pacemaker spike to mitral valve closure was highly significantly correlated with atrioventricular delay in VDD, DVI-L, and DVI-H modes (r = -0.92, p = 0.0001; r = -0.90, p = 0.0001; and r = -0.85, p = 0.0001, respectively) as was the diastolic filling time to a lesser extent (r = -0.73, p = 0.0001; r = -0.69, p = 0.0001; r = -0.61, p = 0.0001, respectively). Events reflecting atrial systole occurred at a later time in the cardiac cycle in the atrial paced vs the atrial sensed mode. Thus changes in atrioventricular delay and pacemaker mode in this group of patients are a strong determinant of the timing and dynamics of left ventricular filling.

Ventricular coupling in constrictive pericarditis

Because of the close anatomic association, the volume or pressure in one ventricle can directly influence the volume and pressure in the other ventricle. Disease states that reduce pericardial compliance should accentuate this coupling between the ventricles. We examined this hypothesis in six dogs. Constrictive pericarditis was induced by injecting an irritant mixture into the pericardial cavity. Three to 4 weeks after this injection, the hearts were removed and placed in cool cardioplegic solution. Balloons were inserted into each ventricle and the pressure and volume changes caused by increasing the contralateral ventricular volume were measured. Compared with that in a control group of four dogs, the coupling between the ventricles was significantly augmented in the group with constrictive pericarditis. All the measured changes in ventricular pressure or volume caused by increasing contralateral ventricular pressure or volume were significantly greater (p less than .05) in the group with constrictive pericarditis. The results of these experiments show increased coupling between the ventricles with constrictive pericarditis, which helps to explain some of the signs and symptoms of constrictive pericarditis.