Atrial Functional Mitral Regurgitation: A JACC: Cardiovascular Imaging Expert Panel Viewpoint

Functional or secondary mitral regurgitation (MR) is associated with increased cardiovascular morbidity and mortality. Mechanistically, secondary MR is attributable to an imbalance between mitral leaflet tethering and closure forces, leading to poor coaptation. The pathophysiology of functional MR is most often the result of abnormalities in left ventricular function and remodeling, seen in ischemic or nonischemic conditions. Less commonly and more recently recognized is the scenario in which left ventricular geometry and function are preserved, the culprit being mitral annular enlargement associated with left atrial dilatation, termed atrial functional mitral regurgitation (AFMR). This most commonly occurs in the setting of chronic atrial fibrillation or heart failure with preserved ejection fraction. There is variability in the published reports and in current investigations as to the definition of AFMR. This paper reviews the pathophysiology of AFMR and focus on the need for a collective definition of AFMR to facilitate consistency in reported data and enhance much-needed research into outcomes and treatment strategies in AFMR.

A novel echocardiographic estimate of pulmonary vascular resistance employing the hydraulic analogy to Ohm’s law

Background

Assessment of pulmonary vascular resistance (PVR) is critical for accurate diagnosis and optimal pharmacotherapy in pulmonary hypertension. We aimed to test the diagnostic performance of a novel, Doppler-based method to evaluate PVR based on Ohm’s law (PVR_echo) using pragmatic estimates of pulmonary capillary wedge pressure (PCWP).

Methods and results

Simultaneous right heart catheterization (RHC) and echocardiography was performed in a derivation cohort of 111 patients in sinus rhythm referred for PH evaluation and PVR_echo independently validated in 238 patients. PVR_echo was calculated using pulmonary artery mean pressure estimates (PAMP_echo) obtained from peak tricuspid gradient employing a fixed right atrial pressure estimate, PCWP_echo was estimated as 10 or 20 mmHg using age-related mitral E/A cut-offs and cardiac output from left ventricular outflow. In the derivation cohort, both PAMP_echo and PCWP_echo estimates demonstrated excellent agreement with catheterization measurements. PVR_echo was highly feasible, demonstrated negligible bias and excellent agreement with PVR_RHC (Bias = −0.58, SD 2.2 mmHg) and outperformed the Abbas method to identify PVR_RHC > 3WU (AUC = 0.85 vs. 0.70; p = 0.02). In the validation cohort, PVR_echo preserved good invasive agreement with negligible bias, displayed strong diagnostic performance (AUC = 0.84) and significant ability to distinguish isolated post-capillary from combined post- and pre-capillary pulmonary hypertension (PH) subgroups (AUC = 0.77).

Conclusion

PVR_echo based on Ohm’s law employing pragmatic estimates of PCWP_echo demonstrates excellent agreement with invasive reference standard measurements and strong diagnostic ability to identify elevated PVR_RHC. This novel approach may be useful during therapy selection to distinguish PH hemodynamic subgroups.

33-year follow-up after valvular surgery for carcinoid heart disease

Background

Valvular surgery for carcinoid heart disease (CaHD) has been found to improve long-term prognosis. Experience is limited and questions about single versus double-valve surgery as well as selection of prosthetic valves remain under debate.

Purpose

We reviewed the surgical experience after valvular surgery for CaHD in our institution, which is a national referral center.

Methods

We reviewed clinical records and echocardiograms. Perioperative death was defined as mortality within 30 days of operation.

Results

Sixty consecutive patients (32 men, 62±9 years) underwent valve surgery between 1986 and 2019, of whom 59/60 had an intestinal carcinoid disease with hepatic metastases. Mean time from diagnosis to heart surgery was 3.8±3.7 years. Preoperatively, 6 patients were in NYHA class I/II, the others were in class III or IV. All 60 surgical procedures involved tricuspid valve replacement (TVR). In 47 cases, the pulmonary valve was treated surgically: Early in the series, five patients underwent pulmonary valvotomy or commissurotomy, and more recently, 42 patients received pulmonary valve replacement (PVR). All valves were replaced with bioprostheses, except for one pulmonary homograft. Concomitant significant aortic and mitral regurgitation occurred in 2 patients who received quadruple valve replacement. Two re-operations were performed due to degeneration of bioprostheses. Mean hospital stay was 13±9 days. Overall 30-day mortality was 11.6% (n=7) but was reduced to 8.3% in the last decade. The overall median survival was 2.2 years. Maximal survival free of reoperation was 18 years, and maximal survival for a single patient was 21 years. Median survival for combined TVR and PVR was significantly better than for single TVR or TVR combined with pulmonary valvotomy (3.0 years vs. 0.94 years, respectively, p=0.02; see Figure).

Preoperatively, left ventricular ejection fraction (EF) was normal in 83%. Severe tricuspid regurgitation was always present. The right ventricle (RV) was dilated (RVD1 49 mm ± 5 mm) as well as the right atrium (60±16 ml/m2). The TAPSE was in normal range (17 to 29 mm). Pulmonary regurgitation was mild, moderate, severe, or indeterminate in 6%, 26%, 51%, and 17% respectively. In 17% the transpulmonary velocity was >2.5 m/s, indicating stenosis. On last available postoperative echo (mean time 2.1 years) EF was found unchanged. RV diameter was nearly normalized (RVD1 41 mm ± 5 mm). TAPSE was reduced (12 mm ± 4 mm). No significant regurgitation was detected in any TVR. There was significant stenosis (mean gradient >5 mmHg) in 23% of the TVR. No regurgitation of significance was detected in any PVR. A mean gradient >20 mmHg was found in 11% of the PVR.

Conclusions

While perioperative risk of valve replacement in CaHD remains substantial, this study shows relatively favourable outcomes of surgical valve replacement with bioprostheses. PVR together with TVR had better outcomes than those undergoing TVR only.

Figure. Survival by Surgical Treatment.

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): Department of Medical Sciences, Uppsala University. Department of Surgical Sciences, Uppsala University

Infektiöse Endokarditis

Infective endocarditis is a severe, mostly bacterial disease characterized by high mortality and morbidity. Both diagnosis and therapy are difficult, and mortality rates have not improved over decades. We review diagnostic and management problems, the disease's modern face in the era of widespread cardiac implants and valve interventions, and current diagnostic and therapeutic recommendations.

Early repolarization, left ventricular diastolic function, and left atrial size in professional soccer players

Recent data have suggested a relation among long-term endurance sport practice, left atrial remodeling, and atrial fibrillation. We investigated the influence of an increased vagal tone, represented by the early repolarization (ER) pattern, on diastolic function and left atrial size in professional soccer players. Fifty-four consecutive athletes underwent electrocardiography, echocardiography, and exercise testing as part of their preparticipation screening. Athletes were divided into 2 groups according to presence or absence of an ER pattern, defined as a ST-segment elevation at the J-point (STE) > or =0.1 mm in 2 leads. For linear comparisons average STE was calculated. Mean age was 24 +/- 4 years. Twenty-five athletes (46%) showed an ER pattern. Athletes with an ER pattern had a significant lower heart rate (54 +/- 9 vs 62 +/- 11 beats/min, p = 0.024), an increased E/e' ratio (6.1 +/- 1.2 vs 5.1 +/- 1.0, p = 0.002), and larger volumes of the left atrium (25.6 +/- 7.3 vs 21.8 +/- 5.0 ml/m(2), p = 0.031) compared to athletes without an ER pattern. There were no significant differences concerning maximum workload, left ventricular dimensions, and systolic function. Univariate regression analysis revealed significant correlations among age, STE, and left atrial volume. In a stepwise multivariate regression analysis age, STE and e' contributed independently to left atrial size (r = 0.659, p <0.001). In conclusion, athletes with an ER pattern had an increased E/e' ratio, reflecting a higher left atrial filling pressure, contributing to left atrial remodeling over time.

NC100100, a new echo contrast agent for the assessment of myocardial perfusion--safety and comparison with technetium-99m sestamibi single-photon emission computed tomography in a randomized multicenter study

BACKGROUND AND HYPOTHESIS

Myocardial contrast echocardiography using second-generation agents has been proposed to study myocardial perfusion. A placebo-controlled, multicenter trial was conducted to evaluate the safety, optimal dose, and imaging mode for NC100100, a novel intravenous second-generation echo contrast agent, and to compare this technique with technetium-99m sestamibi (MIBI) single-photon emission computed tomography (SPECT).

METHODS

In a placebo-controlled, multicenter trial, 203 patients with myocardial infarction > 5 days and < 1 year previously underwent rest SPECT and MCE. Fundamental and harmonic imaging modes combined with continuous and electrocardiogram-- (ECG) triggered intermittent imaging were used. Six dose groups (0.030, 0.100, and 0.300 microliter particles/kg body weight for fundamental imaging; and 0.006, 0.030, and 0.150 microliter particles/kg body weight for harmonic imaging) were tested. A saline group was also included. Safety was followed for 72 h after contrast injection. Myocardial perfusion by MCE was compared with myocardial rest perfusion imaging using MIBI as a tracer.

RESULTS

NC100100 was well tolerated. No serious adverse events or deaths occurred. No clinically relevant changes in vital signs, laboratory parameters, and ECG recordings were noted. There was no significant difference between adverse events in the NC100100 (25.7%) and in the placebo group (17.9%, p = 0.3). Intermittent harmonic imaging using the intermediate dose was superior to all other modalities, allowing the assessment of perfusion in 76% of all segments. Eighty segments (96%) with normal perfusion by SPECT imaging also showed myocardial perfusion with MCE. However, a substantial percentage of segments (61-80%) with perfusion defects by SPECT imaging also showed opacification by MCE. This resulted in an overall agreement of 66-81% and a high specificity (80-96%), but in low sensitivity (20-39%) of MCE for the detection of perfusion defects.

CONCLUSION

NC100100 is safe in patients with myocardial infarction. Intermittent harmonic imaging with a dose of 0.03 microliter particles/kg body weight can be proposed as the best imaging protocol. Myocardial contrast echocardiography with NC 100100 provides perfusion information in approximately 76% of segments and results in myocardial opacification in the vast majority of segments with normal perfusion as assessed by SPECT. Although the discrepancies between MCE and SPECT with regard to the definition of perfusion defects requires further investigation, MCE with NC 100100 is a promising technique for the noninvasive assessment of myocardial perfusion.

Transradial versus transfemoral approach for coronary angiography and intervention in patients above 75 years of age

AIMS

The transradial (TR) approach has potentially lower complication rates than transfemoral (TF) approach coronary angiography. However, it may be technically more challenging, especially in elderly patients with alterations in vascular anatomy. We thus determined success rates, procedural data, and complication rates of TR angiography in comparison to the TF approach in elderly patients in a randomized, prospective trial.

METHODS AND RESULTS

Four hundred consecutive patients >or=75 years with known or suspected coronary artery disease were included in the study. After exclusion of 93 patients with contraindications to the radial approach, 152 patients were randomized to the TR and 155 to TF coronary angiography and intervention. In 13 patients randomized to TR, cross-over to TF was necessary (9%). Total examination time was significantly longer for the TR approach (18.1 vs. 15.0 min, P = 0.009), but no difference was found for fluoroscopy time, number of catheters used, or amount of contrast agent. The rate of major complications (bleeding requiring surgery or transfusion, stroke) was 0% for TR and 3.2% for TF approach (P < 0.001). Minor complications occurred in 1.3% versus 5.8% of patients (P < 0.001).

CONCLUSION

In elderly patients, TR coronary angiography and intervention has a high technical success rate and lower complication rates than the TF approach.

Pulmonary venous flows reflect changes in left atrial hemodynamics during mitral balloon valvotomy

Patients with mitral stenosis have usually blunted pulmonary venous (PV) flow, because of decreased mitral valve area and diastolic dysfunction. The authors compared changes in Doppler PV velocities by using transesophageal echocardiography (TEE) against hemodynamics parameters before and after mitral balloon valvotomy to observe relevance of PV velocities and endsystolic left atrial (LA) pressure-volume relationship. In 25 patients (aged 35 +/- 17 years) with mitral stenosis in sinus rhythm, changes in LA pressure and volumes were compared with PV velocities before and after valvotomy. Mitral valve area, mitral gradients, and deceleration time were obtained. Mitral valve area and mitral gradients changed from 1 +/- 0.2 cm2 and 14.6 +/- 5.4 mmHg to 1.9 +/- 0.3 cm2 and 6.3 +/- 1.7 mmHg, respectively (p<0.001). AR peak reverse flow velocity and AR duration decreased from 29 +/- 13 cm/s and 110 =/- 30 msec to 19 +/- 6 cm/s and 80 +/- 29 msec respectively (p<0.001). Transmitral Doppler E wave deceleration time decreased from 327 +/- 85 to 209 +/- 61 s and cardiac output increased from 4.2 +/- 1.0 to 5.2 +/- 1.1 L/minute (p<0.001). The changes in LA pressure were correlated with changes in S/D (r=0.57, p<0.05). The changes in endsystolic LA pressure-volume relationship were also correlated with changes in S/D (r=0.52, p<0.05). Endsystolic LA pressure-volume relationship decreased after mitral balloon valvotomy, as a result of a large decrease in pressure. PV systolic/diastolic (S/D) waves ratio reflects endsystolic LA pressure-volume relationship and may be used as another indicator of successful valvotomy.

Is Doppler tissue velocity during early left ventricular filling preload independent?

BACKGROUND

Transmitral Doppler flow indices are used to evaluate diastolic function. Recently, velocities measured by Doppler tissue imaging have been used as an index of left ventricular relaxation.

OBJECTIVE

To determine whether Doppler tissue velocities are influenced by alterations in preload.

METHODS

Left ventricular preload was altered in 17 patients (all men, mean (SD) age, 49 (8) years) during echocardiographic measurements of left ventricular end diastolic volume, maximum left atrial area, peak early Doppler filling velocity, and left ventricular myocardial velocities during early filling. Preload altering manoeuvres included Trendelenberg (stage 1), reverse Trendelenberg (stage 2), and amyl nitrate (stage 3). Systolic blood pressure was measured at each stage.

RESULTS

In comparison with baseline, left ventricular end diastolic volume (p = 0.001), left atrial area (p = 0.003), peak early mitral Doppler filling velocity (p = 0.01), and systolic blood pressures (p = 0.001) were all changed by preload altering manoeuvres. Only left ventricular myocardial velocity during early filling remained unchanged by these manoeuvres.

CONCLUSIONS

In contrast to standard transmitral Doppler filling indices, Doppler tissue early diastolic velocities are not significantly affected by physiological manoeuvres that alter preload. Thus Doppler tissue velocities during early left ventricular diastole may provide a better index of diastolic function in cardiac patients by providing a preload independent assessment of left ventricular filling.

[A standardized documentation structure for data documentation in echocardiography. Work Team on Standards and LV Function of the Work Group on Cardiovascular Ultrasound of the German Society of Cardiology, Heart and Circulation Research]

Presently, there are no well-defined standards for documentation of echocardiographic studies. Nevertheless, standards are essential to provide comparability of data and to realize electronic communication, both essential for quality management in echocardiography. Therefore, the working group "Standards and LV function" of the German Society of Cardiology developed a consensus for documentation of echocardiographic studies. In the present paper this consensus is presented and illustrated by typical clinical examples. Additionally, a prototype of a user-oriented software based on this data set is presented. The complete data set for transesophageal and transthoracic echocardiography and the software prototype can be downloaded at http:@echo.ma.uni-heidelberg.de.

Accuracy and feasibility of contrast echocardiography for detection of perfusion defects in routine practice: comparison with wall motion and technetium-99m sestamibi single-photon emission computed tomography. The Nycomed NC100100 Investigators

OBJECTIVES

We sought to assess the feasibility and accuracy of myocardial contrast echocardiography (MCE) using standard imaging approaches for the detection of perfusion defects in patients who had a myocardial infarction (MI).

BACKGROUND

Myocardial contrast echocardiography may be more versatile than perfusion scintigraphy for identifying the presence and extent of perfusion defects after MI. However, its reliability in routine practice is unclear.

METHODS

Fundamental or harmonic MCE was performed with continuous or triggered imaging in 203 patients with a previous MI using bolus doses of a perfluorocarbon-filled contrast agent (NC100100). All patients underwent single-photon emission computed tomography (SPECT) after the injection of technetium-99m (Tc-99m) sestamibi at rest. Quantitative and semiquantitative SPECT, wall motion and digitized echocardiographic data were interpreted independently. The accuracy of MCE was assessed for detection of segments and patients with moderate and severe sestamibi-SPECT defects, as well as for detection of patients with extensive perfusion defects (>12% of left ventricle).

RESULTS

In segments with diagnostic MCE, the segmental sensitivity ranged from 14% to 65%, and the specificity varied from 78% to 95%, depending on the dose of contrast agent. Using both segment- and patient-based analysis, the greatest accuracy and proportion of interpretable images were obtained using harmonic imaging in the triggered mode. For the detection of extensive defects, the sensitivity varied from 13% to 48%, with specificity from 63% to 100%. Harmonic imaging remained the most accurate approach. Time since MI and SPECT defect location and intensity were all determinants of the MCE response. The extent of defects on MCE was less than the extent of either abnormal wall motion or SPECT abnormalities. The combination of wall motion and MCE assessment gave the best balance of sensitivity (46% to 55%) and specificity (82% to 83%).

CONCLUSIONS

Although MCE is specific, it has limited sensitivity for detection of moderate or severe perfusion defects, and it underestimates the extent of SPECT defects. The best results are obtained by integration with wall motion. More sophisticated methods of acquisition and interpretation are needed to enhance the feasibility of this technique in routine practice.

Stenotic lesions

Images

Recent progress in quantitative echocardiography

Substantial progress has been made recently in quantitating a variety of functional or morphologic parameters with echocardiography. Doppler techniques for measuring regurgitant flow rate and regurgitant orifice area in mitral and tricuspid regurgitation have become well established, along with other Doppler measures of regurgitation severity, such as proximal jet width. Doppler measurement of diastolic flow propagation in the left ventricle is emerging as a promising, albeit fascinatingly complex way of looking at diastolic function. Doppler velocimetry has been extended to wall motion, yielding color maps of tissue, an entirely new tool for assessing myocardial function and its timing. In the field of two-dimensional data processing, automatic on-line boundary detection based on integrated ultrasound backscatter has been used for volume and cardiac output calculations. Finally, three-dimensional reconstruction of cross-sectional images now has been well validated for in vivo measurements of heart cavity volumes and masses.