Predictive value of prominent pulmonary arterial wedge V waves in assessing the presence and severity of mitral regurgitation

Emergency Transcatheter Repair for Anterior Leaflet Tear Following Percutaneous Balloon Mitral Valvuloplasty

We present the case of a 66-year-old woman who developed severe mitral regurgitation from rupture of the anterior mitral valve leaflet following percutaneous balloon mitral valvuloplasty. Emergency transcatheter mitral valve repair was used to reduce the severity of mitral regurgitation and facilitate definitive surgical treatment. (Level of Difficulty: Advanced.).

Invasive hemodynamics are equivocal for functional outcomes after MitraClip

Objectives

To evaluate invasive hemodynamics in assessing MC therapy success as well as evaluate its effectiveness as a predictor of functional outcomes.

Background

Mitral regurgitation grade is a poor predictor of functional outcomes after a MitraClip. There is a paucity of data on invasive hemodynamics as a predictor of outcomes.

Methods

Sixty-nine patients underwent MC between 2015 and 2018 at the University of Minnesota Medical Center and were retrospectively analyzed. Invasive hemodynamics were performed before and after device deployment with transesophageal echocardiographic guidance. Statistical analysis was performed using STATA version 16. Student's t test was used for continuous variables and Pearson's chi-squared test for categorical variables. Mann-Whitney test was performed for continuous variables where data were not normally distributed. Logistic and linear regression were used to investigate relationships between variables and outcomes.

Results

A total of 69 patients were included in the study. The mean age was 83 (75-87) years and 38 (55%) were male. Eighty-one percentage had >/= NYHA III symptoms. Eighty-seven percentage had severe MR. Pulmonary capillary wedge pressure was 20 (15-24). Overall, there was significant improvement in left atrial pressure including mean left atrial pressure index, MR, and NYHA class after MC (<.001). There was no significant association between invasive hemodynamics (including left atrial mean pressure index or its reduction rate) and functional outcomes (p = NS). MR grade was also not predictive of functional outcomes.

Conclusion

Left atrial pressure may not be a significant predictor of functional outcomes, and, in isolation, may not be an improvement over MR grade.

Exercise Hemodynamic Profiling Is Associated With Outcome in Patients Undergoing Percutaneous Mitral Valve Repair

BACKGROUND

Percutaneous mitral valve repair (PMVR) in high-risk patients is currently controversial, especially in those with secondary mitral regurgitation (MR). Exercise pulmonary hemodynamics may help to unmask cardiac dysfunction as well as the dynamic impact of MR. The present study sought to explore the clinical impact of preprocedural exercise right heart catheterization (RHC) for the selection of patients who could most benefit from PMVR.

METHODS

Sixty-eight patients with symptomatic primary and secondary MR and exercise RHC before PMVR were included in this retrospective analysis of the association of exercise RHC parameters with survival and improvement in New York Heart Association class within 12 months.

RESULTS

Median patient age was 77 years (±8.5), 37% were female, and 81% presented with New York Heart Association class III. A total of 65% of the patients had left ventricular ejection fraction <55%. MR was severe in 49% and moderate-to-severe in 51%. Twenty-two patients (32%) died within the follow-up period of 19 months (interquartile range, 9-32); they had a lower rise (Δ) in the V-wave on pulmonary artery wedge pressure tracings. Patients with ΔV-wave ≥17 mm Hg had a reduced risk of death after PMVR (hazard ratio, 0.11 [95% CI, 0.04-0.33], P<0.001), independent of age, frailty index, and workload during RHC. A higher ΔV-wave was also associated with New York Heart Association improvement (odds ratio, 1.14 [95% CI, 1.07-1.24]; P<0.001), and 79% of patients with ∆V-wave ≥15 mm Hg were in New York Heart Association class I or II at follow-up (<15 mm Hg: 28%). These results were for the most part confirmed in the subgroup of patients with secondary MR (65%).

CONCLUSIONS

In our cohort of patients with indication for PMVR, preprocedural exercise RHC was able to identify patients with an unfavorable outcome. Further studies with larger patient numbers are warranted before this approach can be implemented in a structured diagnostic workup of patients under evaluation for PMVR.

The contemporary pulmonary artery catheter. Part 1: placement and waveform analysis

Nowadays, the classical pulmonary artery catheter (PAC) has an almost 50-year-old history of its clinical use for hemodynamic monitoring. In recent years, the PAC evolved from a device that enabled intermittent cardiac output measurements in combination with static pressures to a monitoring tool that provides continuous data on cardiac output, oxygen supply and-demand balance, as well as right ventricular (RV) performance. In this review, which consists of two parts, we will introduce the difference between intermittent pulmonary artery thermodilution using cold bolus injections, and the contemporary PAC enabling continuous measurements by using a thermal filament which at random heats up the blood. In this first part, the insertion techniques, interpretation of waveforms of the PAC, the interaction of waveforms with the respiratory cycle and airway pressure as well as pitfalls in waveform analysis are discussed. The second part will cover the measurements of the contemporary PAC including measurement of continuous cardiac output, RV ejection fraction, end-diastolic volume index, and mixed venous oxygen saturation. Limitations of all of these measurements will be highlighted there as well. We conclude that thorough understanding of measurements obtained from the PAC are the first step in successful application of the PAC in daily clinical practice.

Disproportionate secondary mitral regurgitation: myths, misconceptions and clinical implications

Secondary (functional) mitral regurgitation (SMR) most commonly arises secondary to left ventricular (LV) dilation/dysfunction. The concept of disproportionately severe SMR was proposed to help explain the different results of two randomised trials of transcatheter edge-to-edge mitral valve repair (TEER) versus medical therapy. This concept is based on the fact that effective regurgitant orifice area (EROA) depends on LV end-diastolic volume (LVEDV), ejection fraction, regurgitant fraction and the velocity-time integral of SMR. This review focuses on the haemodynamic framework underlying the concept and the myths and misconceptions arising from it. Each component of EROA/LVEDV is prone to measurement error which can result in misclassification of individual patients. Moreover, EROA is typically measured at peak systole rather than its mean value over the duration of MR. This can result in physiologically impossible values of EROA or regurgitant volume. Although the EROA/LVEDV ratio (1) emphasises that grading MR severity needs to consider LV size and function and (2) helps explain the different outcomes between COAPT and MITRAFR, there are important factors that are not included. Among these are left atrial compliance, LV pressure and ejection fraction, pulmonary hypertension, right ventricular function and tricuspid regurgitation. Because medical therapy can reduce LV volumes and improve both LV function and SMR severity, the key to patient selection is forced titration of neurohormonal antagonists to the target doses that have been proven in clinical trials (along with cardiac resynchronisation when appropriate). Patients who continue to have symptomatic severe SMR after doing so should be considered for TEER.

Urgent mechanical circulatory support and transcatheter mitral valve repair for refractory hemodynamic compromise

Patients presenting with hemodynamic instability attributable to left ventricular systolic dysfunction and concomitant severe mitral regurgitation (MR) are increasingly recognized and pose complex management challenges. Surgical therapy is typically precluded owing to prohibitive mortality. The role of percutaneous mechanical circulatory support in such cases is well established; however, such interventions may be neither sufficient to achieve optimal stability nor prove definitive. The advent of novel catheter-based mitral repair modalities now offers primary decisive therapeutic intervention. Three cases of cardiogenic shock with severe MR illustrate the salutary hemodynamic and clinical responses to percutaneous mechanical support and valve repair by mitral clip.

Contribution of the left atrial remodeling to the elevated pulmonary capillary wedge pressure in patients with WHO Group II pulmonary hypertension

BACKGROUND

The contribution of progressive left atrial (LA) enlargement to elevated pulmonary capillary wedge pressure (PCWP) in patients with WHO Group II pulmonary hypertension (PH) has not been well studied. We hypothesized that progressive LA enlargement is associated with increased PCWP.

METHODS

A cross-sectional retrospective cohort consisted of 166 patients with HF and WHO Group II PH, confirmed by right heart catheterization (RHC). LA anteroposterior dimension and volume were measured on TTE. PCWP and other hemodynamic parameters were measured by RHC. Univariate and multivariate logistic regression models were used for analysis.

RESULTS

LA enlargement was associated with advanced age, increased BMI, and LV ejection fraction < 40%. PCWP was progressively increased in patients with dilated LA: 16.9 ± 7.4 mmHg in normal LA, 17.6 ± 7.2 mmHg in mildly dilated LA, 22.6 ± 6.3 mmHg in moderately and 22 ± 7.6 in severely dilated LA (p < 0.001). In multiple logistic regression, after adjustment for echocardiographic and clinical variables, severe LA enlargement was independently predictive of elevated PCWP (OR 3.468; 95% CI 1.046-11.504; p = 0.042). After excluding significant mitral regurgitation, progressive LA dilatation was associated with higher PCWP V-wave amplitude: from 21.3 ± 10.4 mmHg in patients with normal LA size, to 30.9 ± 11.7 mmHg in moderately dilated and 31.0 ± 11.6 mmHg in severely dilated LA (p < 0.001).

CONCLUSIONS

In patients with HF and WHO Group II PH, progressive LA enlargement was independently associated with elevated PCWP. After excluding significant mitral regurgitation, LA enlargement was also associated with increased V-wave amplitude, indicative of decreased atrial compliance.

The Accuracy of a Large V Wave in the Pulmonary Capillary Wedge Pressure Waveform for Diagnosing Current Mitral Regurgitation

Background: Large V waves in the pulmonary capillary wedge pressure (PCWP) waveform traditionally indicate severe mitral regurgitation (MR). However, our understanding of MR etiology and hemodynamics has changed in recent decades. Objectives: We aimed to reevaluate the association between large V waves and current MR to determine whether traditional large V wave criteria remain optimal. Method: We reviewed 1,964 right heart catheterizations (RHCs) performed at our institution from 2010 to 2017, and retrospectively selected 126 patients with sinus rhythm who underwent echocardiography within 2 days (0.3 ± 0.5 days) of the RHC. The diagnostic accuracy of 3 traditional criteria for large V waves was assessed, and the optimal cut-off points were determined as those with the maximal Youden indices. Results: Severe MR was observed on echocardiography in 26 (21%) patients, including 15 (58%) with Carpentier classification type II MR and 11 (42%) with type IIIB MR. Large V waves, defined as a difference between the peak V wave and mean PCWP ≥10 mm Hg, had a high specificity of 94% (95% confidence interval: 87–98%), but a low sensitivity of 27% (12–48%) for diagnosing severe MR. The optimal cut-off point for the V wave was 3 mm Hg above the mean PCWP, with a sensitivity of 73% (52–88%) and a specificity of 64% (54–73%). Conclusions: For diagnosing current MR, the cut-off point for a large V wave should be reduced from that previously employed for rheumatic valvular heart disease. This information may be useful in guiding contemporary transcatheter therapies for MR under RHC monitoring.

Invasive Hemodynamics of Valvular Heart Disease

In the current era, diagnosis and follow-up of valvular heart disease is performed noninvasively using echocardiography. In some cases, the results of echocardiographic evaluation are inconclusive or discrepant with the patient's clinical symptoms. In such cases, a well-planned and executed cardiac catheterization is invaluable to clarify the clinical dilemma and assist in planning further management. This article reviews the indications, technique, and interpretation of cardiac catheterization in the setting of valvular stenosis and regurgitation.

Quantification of mitral regurgitation during percutaneous mitral valve repair: added value of simultaneous hemodynamic and 3D echocardiographic assessment

The objective of this study was to investigate the usefulness of intraprocedural hemodynamic monitoring for MR evaluation during pMRV. Assessment of mitral regurgitation (MR) during percutaneous mitral valve repair (pMVR) procedure is challenging. 3D color Doppler allows exact quantification of MR, but is technically demanding. Sixty patients with moderate to severe MR (14 with structural and 46 functional MR) were included in the study. Intraprocedural pressure curves were continuously obtained in the left atrium (LA) and left ventricle (LV). Transesophageal echocardiography was performed using 3D color Doppler derived mean vena contracta area (VCA_mean) and mitral regurgitation volume (RegVol) to quantify MR severity before and after each clip implantation. In the entire patient group, strongest correlations were observed firstly between VCA and the raise of the ascending limb of the left atrial V pressure wave (V_ascend; r = 0.58, p < 0.001) and secondly between the difference of peak V wave pressure and mean LA pressure divided by systolic LV pressure [(V_peak - LA_mean) - LV_systole; r = 0.53, p < 0.001]. In patients with structural MR, the highest area under the ROC curve for prediction of mild MR (VCA_mean < 0.2 cm² and RegVol < 30 ml) after clip implantation was found for V_ascend (AUC 0.89, p < 0.001) whereas in functional MR calculation of (V_peak - LA_mean) - LV_systole showed the highest predictive value (AUC 0.69, p = 0.003). Invasive pressure monitoring can give a direct feedback with regard to the success of clip placement during pMVR.

Invasive assessment of mitral regurgitation: Comparison of hemodynamic parameters

OBJECTIVES

We sought to analyze several new hemodynamic characteristics which address the interplay of left atrial (LA) and left ventricular (LV) pressures, as well as to re-analyze several other V wave characteristics employed in the determination of mitral regurgitation (MR) severity in order to determine which, if any, had adequate correlation with grade of MR for clinical utility.

BACKGROUND

Invasive assessment of mitral regurgitation includes analysis of intracardiac pressures and LV angiography. The V wave, when obtained from the pulmonary capillary wedge position (PCWP), and its various characteristics are believed to be of limited value for prediction of MR severity.

METHOD

We analyzed the transeptal pressure tracings of patients with various degrees of MR. Several relationships from the simultaneous pressure-time curves of the LA and LV were defined. Biplane left ventricular angiography was used to grade MR. Correlation between each parameter and MR grade was determined by calculating a Pearson correlation coefficient.

RESULTS

The ratio of the area under the V wave to the LV systolic area (V(a)/LV(a)) best correlates with the degree of MR with a Pearson correlation coefficient of 0.60. The V(a)/LV(a) was significantly lower in patients with 0-1+ MR compared to > or =2+ MR (0.14 vs. 0.23 p = 0.002).

CONCLUSIONS

Invasive hemodynamic assessment of MR severity could be enhanced by calculating our new ratio, V(a)/LV(a), due to its ability to account for LV work that is lost to the LA with a proportional decrease in forward or useful LV work with progressively increasing severity of MR.

Lung water, hemodynamics and dyspnea before and after valvuloplasty in mitral stenosis

The investigation was to elucidate the role of the reduction of extravascular pulmonary fluid in the immediate symptomatic improvement and its impact on hemodynamics in patients with mitral stenosis treated by percutaneous transluminal valvuloplasty.

METHODS

In a prospective study of 12 patients with severe mitral stenosis extravascular pulmonary fluid volume was determined by a combined dye and thermodilution technique (COLD Z-021(TM) Version 5.x, Pulsion((R))) before and after valvuloplasty. Cardiac output, left atrial pressures, atrial V-waves, diastolic transmitral gradients and their respiratory changes were measured. Dyspnea was assessed by validated questionnaires.

RESULTS

Symptomatic improvement correlated (r=0. 808) with a decrease of extravascular lung water, but not with either an increase or a decrease of cardiac output or left atrial filling pressures. The decrease of the lung water index may be predicted from the lung water index before valvuloplasty, the final left atrial mean pressure and the cardiac index prior to intervention. The change of the mean difference between inspiratory and expiratory mitral gradient demonstrated a significant inverse correlation with the change of mean left atrial filling pressures (r=-0.778) and with extravascular lung water after valvuloplasty (r=-0.871).

CONCLUSION

There is a complex relationship between left atrial filling pressures, extravascular lung water, respiratory changes of gradients, and dyspnea that need further investigation.

Predictive value of prominent right atrial V waves in assessing the presence and severity of tricuspid regurgitation

Neither "prominent" right atrial V waves nor an elevated mean right atrial pressure reliably predicts the presence of moderate or severe tricuspid regurgitation. On the other hand, the absence of prominent right atrial V waves and an elevated mean right atrial pressure are relatively specific for the absence of moderate or severe tricuspid regurgitation.

Determinants of pulmonary venous flow reversal in mitral regurgitation and its usefulness in determining the severity of regurgitation

Pulmonary venous flow (PVF) reversal is observed in mitral regurgitation (MR) and can be detected by Doppler echocardiography. However, the determinants of PVF alterations in MR have not been analyzed with simultaneous quantitative methods, and the diagnostic accuracy of flow reversal is uncertain. Prospectively, in 128 patients with isolated MR of various degrees (regurgitant fraction 4% to 81%), Doppler echocardiography was used to measure PVF velocity simultaneously to quantify MR by 2 methods and to perform a comprehensive hemodynamic assessment. Systolic PVF velocity was 4 +/- 56 cm/s (systolic flow reversal in 39 patients) and showed the strongest correlations with mitral effective regurgitant orifice (r = -0.56, p <0.0001). In multivariate analysis, larger effective regurgitant orifice (p <0.0001), eccentric jets (p = 0.0023), longer jets (p = 0.0033), and lower mitral regurgitant velocity (p = 0.0015) were independent determinants of decreased systolic PVF velocity. In organic MR, increased filling pressures were associated with systolic PVF reversal. Blunted systolic flow was associated with shorter mitral deceleration time (p <0.0001) and enlarged left atrium (p = 0.0007). For the diagnosis of severe MR (regurgitant orifice > or = 35 mm2, regurgitant fraction > or = 50%), systolic flow reversal sensitivity was 61% and 60%, and specificity was 92% and 85%, respectively. Among 29 patients in whom surgery demonstrated severe mitral lesions, 12 (41%) had no systolic flow reversal preoperatively. In patients with MR, the determinants of systolic PVF are complex and, in addition to the degree of MR, include the hemodynamic consequences of MR, jet characteristics, left ventricular filling, and left atrial volume alterations. Consequently, systolic PVF reversal is a useful sign of severe MR but of relatively low sensitivity, emphasizing the importance of quantifying MR.

What does the left atrial v wave signify during balloon commissurotomy of mitral stenosis?

Left atrial v-wave amplitude has been associated with the presence and severity of chronic mitral regurgitation (MR) but it has not been evaluated for the detection of acute MR. We evaluated the left atrial v-wave amplitude of 205 consecutive patients with mitral stenosis immediately before and after stepwise, incremental balloon mitral commissurotomy to determine predictors of large v waves at baseline and an increase in v-wave amplitude after balloon commissurotomy. The sensitivity and specificity of an increase in v-wave amplitude for detecting worsening and severe MR were determined. A large v wave was present in 44% of patients before balloon commissurotomy and was predicted by age, mean left atrial pressure, mean transmitral gradient, mean pulmonary artery pressure, and angiographic severity of MR. There was a strong inverse correlation between v-wave amplitude and calculated left atrial compliance (r = -0.92). An increase in v-wave amplitude after balloon commissurotomy was associated with an increasing probability of worsening or severe MR. This indicator had a sensitivity, specificity, and positive and negative predictive values of 35%, 91%, 64%, 75%, respectively, for detecting any increase in MR. For the detection of severe MR, the sensitivity was 79%, specificity 89%, positive predictive value 42%, and negative predictive value 98%. Thus, left atrial v-wave amplitude reflects left atrial compliance and severity of mitral stenosis before balloon commissurotomy. An increase in v-wave amplitude is an insensitive but very specific indicator of worsening or severe MR during stepwise, incremental balloon mitral commissurotomy.

Relationship between pulmonary capillary wedge V wave and transmitral and pulmonary venous flow velocity patterns in various heart diseases

BACKGROUND

A large V wave in a pulmonary capillary wedge pressure (PCWP) tracing is characteristic of mitral regurgitation. However, the V wave is often increased in patients without or with no significant mitral regurgitation.

METHODS AND RESULTS

The V wave was in the PCWP tracing investigated in 65 patients using transmitral flow (TMF) and pulmonary venous flow (PVF) velocity patterns obtained by transesophageal pulsed Doppler echocardiography. A large V wave was defined if the peak V wave minus the mean PCWP (V-mPCWP) was greater than 7 mmHg. Three study groups were formed: 15 patients with large V waves and significant mitral regurgitation, 15 patients with large V waves with no significant mitral regurgitation, and 35 patients with small V waves. The mPCWP and left ventricular end-diastolic pressure were greatest in the group with large V waves and no significant mitral regurgitation. Peak early diastolic TMF and PVF velocities were significantly greater in the two groups with large V waves. The peak second systolic PVF velocity was lowest in the group with large V waves and significant mitral regurgitation, followed by the group with large V waves and no significant mitral regurgitation. The V-mPCWP was positively correlated with the peak early diastolic TMF and PVF velocities and negatively correlated with the peak second systolic PVF velocities. Additionally, mitral regurgitation severity in patients with large V waves and significant mitral regurgitation was positively correlated with the peak early diastolic TMF and PVF velocities and negatively correlated with the peak second systolic PVF velocity.

CONCLUSIONS

These results suggest that large V waves in PCWP tracings appear not only in severe mitral regurgitation, but also in any condition with markedly elevated left ventricular end-diastolic pressure. Combined analysis of the TMF and PVF velocity patterns is helpful in determining the etiology of these hemodynamic abnormalities.