Mitral Annular Reduction Research Articles

Epicardial Posterior Papillary Muscle Repositioning with Mitral Annular Reduction for FIMR Treatment: Initial Ex Vivo Heart Model Study.

High recurrent functional ischemic mitral regurgitation (FIMR) has been observed after annuloplasty. Since annuloplasty alone could not prevent late recurrent FIMR or improve the survival rate after CABG, adjunctive subvalvular opt for better treatment tailored for each individual patient. Ex vivo ovine heart models with annular dilatation and PPM displacement were used for analysis of mitral regurgitation (MR) flow, left ventricular and annular geometry after treatment by mitral annular reduction alone (MA, nMA = 12) or combined with epicardial PPM repositioning (MA+PPM, nMA+PPM=13). MR significantly was reduced from baseline in both the MA (P = .03) and MA+PPM (P = .02) groups, but was not significantly different between the groups. The septo-lateral mitral annular distance decreased after applying both methods (MA group P = .005; MA+PPM group P = .05). The tethering α angle of the APM in the frontal plane significantly increased from baseline in the MA+PPM group (P = .027). Furthermore, the MA+PPM group had a larger APM and PPM α angle in the frontal plane compared with the MA group after reducing the MR (P = .04). There were no statistically significant changes in tethering angles found in the MA group compared with baseline. MR reduction correlated with percentage decrease of septo-lateral mitral annular distance (rs = 0.51, P = .01), the percentage decrease of fibrosa-PPM distance (rs = 0.43, P = .03), and the percentage increase of the PPM anterior displacement (rs = -0.41, P = .04). The decreased tethered angle of the PPM referred to the annulus, and the decreased interpapillary muscles distance suggested the PPM was repositioned inward and toward the septal annulus by the epicardial pushing pad. Epicardial repositioning of the PPM adjunct with mitral annular reduction facilitated leaflet coaptation without the risk of overlying restriction of the mitral annular orifice.

The REDUCE FMR Trial: A Randomized Sham-Controlled Study of Percutaneous Mitral Annuloplasty in Functional Mitral Regurgitation

ObjectivesThis study sought to evaluate the effects of the Carillon device on mitral regurgitation severity and left ventricular remodeling. BackgroundFunctional mitral regurgitation (FMR) complicates heart failure with reduced ejection fraction and is associated with a poor prognosis. MethodsIn this blinded, randomized, proof-of-concept, sham-controlled trial, 120 patients receiving optimal heart failure medical therapy were assigned to a coronary sinus-based mitral annular reduction approach for FMR or sham. The pre-specified primary endpoint was change in mitral regurgitant volume at 12 months, measured by quantitative echocardiography according to an intention-to-treat analysis. ResultsPatients (69.8 ± 9.5 years of age) were randomized to either the treatment (n = 87) or the sham-controlled (n = 33) arm. There were no significant differences in baseline characteristics between the groups. In the treatment group, 73 of 87 (84%) had the device implanted. The primary endpoint was met, with a statistically significant reduction in mitral regurgitant volume in the treatment group compared to the control group (decrease of 7.1 ml/beat [95% confidence interval [CI]: −11.7 to −2.5] vs. an increase of 3.3 ml/beat [95% CI: −6.0 to 12.6], respectively; p = 0.049). Additionally, there was a significant reduction in left ventricular volumes in patients receiving the device versus those in the control group (left ventricular end-diastolic volume decrease of 10.4 ml [95% CI: −18.5 to −2.4] vs. an increase of 6.5 ml [95% CI: −5.1 to 18.2]; p = 0.03 and left ventricular end-systolic volume decrease of 6.2 ml [95% CI: −12.8 to 0.4] vs. an increase of 6.1 ml [95% CI: −1.42 to 13.6]; p = 0.04). ConclusionsThe Carillon device significantly reduced mitral regurgitant volume and left ventricular volumes in symptomatic patients with functional mitral regurgitation receiving optimal medical therapy. (Carillon Mitral Contour System for Reducing Functional Mitral Regurgitation [REDUCE FMR]; NCT02325830)

Mitral annular reduction with subablative therapeutic ultrasound

Mitral annular reduction with subablative therapeutic ultrasound

Clinical implications of thrombocytopenia among patients undergoing intra-aortic balloon counterpulsation in the coronary care unit

Clinical implications of thrombocytopenia among patients undergoing intra-aortic balloon counterpulsation in the coronary care unit

Evaluation of sirolimus-eluting stents and Titan2 bio-active stents performance by optical coherence tomography: a window on the importance of nitric oxide for strut coverage

Evaluation of sirolimus-eluting stents and Titan2 bio-active stents performance by optical coherence tomography: a window on the importance of nitric oxide for strut coverage

Mitral annular reduction with subablative therapeutic ultrasound: pre-clinical evaluation of the ReCor device

To evaluate the potential for mitral annular (MA) size reduction using a novel device utilising therapeutic ultrasound (TU).The ReCor device (ReCor Medical, Inc., Ronkonkoma, NY, USA, Investigational device, not for use in human application) was studied in a closed chest canine animal model (35 dogs). Under fluoroscopy, a 12 Fr TU balloon catheter was advanced into the left atrium (transseptal approach). The TU balloon was inflated with contrast-saline, positioned at the MA and energy delivered circumferentially, to heat the tissue locally. Five TU applications were delivered (at least 60W for at least 40 sec). Relative to baseline, mitral valve annular diameter reduction (measured by transthoracic echocardiography) was 8.4% immediately post procedure(p<0.001), 8.6% at one week (p<0.001), 8.8% at two weeks (p<0.001), 9.3% at three weeks (p<0.001), 10.8% at four weeks (p<0.001), 8.6% at three months (p<0.001) and 5.7% at six months (p<0.001). Histology showed an increase in elastin associated with tissue thickening at the annular level. Transmission electron microscopy demonstrated a decrease in diameter of individual collagen fibres in treated regions compared to controls.Therapeutic ultrasound (TU) energy application to the mitral annulus is feasible percutaneously. A reduction in annular dimensions occurs immediately and appears to be durable without peri-annular damage.

AS-41: Mitral Annular Reduction with Subablative Therapeutic Ultrasound

Mitral regurgitation (MR) is a common problem and results in high health care consumption and increased morbidity and mortality. Delivering energy at subablative temperatures appears to produce contraction of the mitral valve annulus (MA) and may reduce mitral regurgitation by improving leaflet coaptation. It was hypothesized that therapeutic ultrasound (TU) from the ReCor (ReCor, Ronkonkoma, NY, USA; Investigational device, not for use in human application) device could result in such MA size reduction.

How much septal–lateral mitral annular reduction do you get with new ischemic/functional mitral regurgitation annuloplasty rings?

Disproportionate reduction of the mitral septal-lateral annular dimension is the goal in the surgical treatment of ischemic or functional mitral regurgitation and avoids the need for ring "downsizing." How much the new annuloplasty rings designed for patients with ischemic/functional mitral regurgitation reduce annular septal-lateral dimension, however, is proprietary information and debated. Outer and inner septal-lateral and commissure-commissure diameters of all available sizes of Edwards GeoForm, Edwards IMR ETlogix (both Edwards Lifesciences, Irvine, Calif), St Jude Medical Rigid Saddle Annuloplasty Ring (St Jude Medical, Inc, St Paul, Minn), and Medtronic Profile 3D (Medtronic, Minneapolis, Minn) annuloplasty rings with and without the fabric covering were measured with electronic calipers. These rings were compared with a Carpentier-Edwards Physio ring (Edwards Lifesciences) to assess the relative amount of septal-lateral and commissure-commissure dimension change. Average fractional changes (% +/-1 standard deviation) versus the Physio ring were calculated. The GeoForm provided the greatest outer septal-lateral reduction relative to Physio ring (-24% +/- 2%), followed by the IMR ETlogix (-9% +/- 2%) and Profile 3D (-8% +/- 5%). The septal-lateral diameter of the Rigid Saddle Annuloplasty Ring was similar to that of the Physio ring (+1% +/- 3%). Although commissure-commissure outer diameters of the IMR ETlogix, Rigid Saddle Annuloplasty Ring, and Profile 3D were similar to that of the Physio ring (0% +/- 2%, +4% +/- 3%, and +3% +/- 4%, respectively), the GeoForm had a larger commissure-commissure dimension (+12% +/- 2%). The inner diameter septal-lateral reductions were even more pronounced. Relative to the Physio ring, the GeoForm has the most outer and inner septal-lateral reduction but larger commissure-commissure dimension; the IMR ETlogix and Profile 3D provide a moderate degree of septal-lateral reduction without affecting commissure-commissure dimension, and Rigid Saddle Annuloplasty Ring septal-lateral and commissure-commissure diameters are similar to those of the Physio ring. Knowing the degree of disproportionate septal-lateral downsizing inherent in each ring type will help guide surgical decision making.

The Synergism Between Atrial Fibrillation and Heart Failure

Background Atrial fibrillation (AF) is a common comorbidity in heart failure (HF) patients and is classically associated with acceleration in the rate of HF progression. The precise mechanism for this interaction is unclear, but comprises “bidirectional” aspects in which AF promotes HF and HF also increases the likelihood of AF. We therefore studied the relationship between AF in an ovine model of pacing-induced congestive HF, in an attempt to identify the mechanisms that underpin the apparent synergistic relationship between AF and HF. Methods and Results Sixteen adult sheep were paced at 190 beats/min for 21 days (HF). AF was induced in 8 of these animals at 14 days' pacing using programmed extrastimuli (HF + AF). Left ventricular hemodynamics and the pattern of cardiac neurohormonal activation, via coronary sinus (CS) sampling, were determined at rest and during submaximal exercise testing in both groups at 21 days and after AF reversion (by atrial defibrillation) at 21 days. CS norepinephrine (NE), endothelin (ET-1), and brain natriuretic peptide (BNP) levels were significantly increased in HF + AF animals, whereas LV end-diastolic pressure (EDP) and LV dP/dt max were significantly reduced compared with moderate HF alone. Cardioversion significantly reduced CS NE and BNP levels and improved contractility in AF + HF animals. In a further 6 animals, we explored the mechanism by which HF increases susceptibility to AF, with specific emphasis on the influence of functional mitral regurgitation. The elimination of MR in HF animals using a percutaneous mitral annular reduction device significantly decreased the inducibility of AF. Conclusions AF induction significantly depresses left ventricular function and causes activation of myocardial neurohormones. In conjunction, the presence of functional MR increases susceptibility to AF and this may be attenuated by MR reduction by percutaneous mitral annular reduction.

Coronary Sinus in the Management of Functional Mitral Regurgitation

The past 5 years have seen the introduction into the preclinical arena of myriad devices for the potential treatment of functional and ischemic mitral regurgitation by a percutaneous approach.1 A number of the device concepts have taken advantage of the relatively easy access to the posterior annulus of the mitral valve provided by the coronary sinus. Although attractive on initial consideration as a delivery route for devices that remodel the posterior mitral annulus, a number of potential shortcomings to this approach may ultimately limit its clinical success. Article p 377 Annular remodeling of the mitral valve for functional mitral regurgitation (FMR) has been demonstrated to have short-term and some intermediate-term efficacy in the clinical surgical setting.2 The pathophysiology of FMR in patients with dilated cardiomyopathy is central regurgitation caused by failure of mitral leaflet coaptation. The causes of this malcoaptation are multifactorial and include annular dilatation and ventricular dilation, which cause apical distraction of the papillary muscles, producing tethering of the mitral leaflets. Although the whole annulus has been demonstrated to dilate in FMR, there is a disproportionate increase in the anterior-posterior or septal-lateral diameter.3,4 The basic premise behind the surgical approach is that through the use of an undersized ring to overcorrect the dilation of the mitral annulus, both the annular dilatation and the tethering of the leaflets from apical papillary muscle displacement can be treated. The tenets for optimal surgical …

Feasibility and short‐term efficacy of percutaneous mitral annular reduction for the therapy of functional mitral regurgitation in patients with heart failure

While functional mitral regurgitation (MR) commonly accompanies heart failure and contributes to heart failure progression, mitral repair in the setting of HF is not routinely practiced because of the attendant significant morbidity and mortality. This limitation has fostered the development of percutaneous devices to reduce MR, and our group has recently reported the short- and long-term effectiveness of a percutaneous mitral annuloplasty device placed in the coronary sinus (Percutaneous Mitral Annuloplasty Device (PMAD), Cardiac Dimensions(R), Inc., Kirkland, WA) in reducing MR in experimental animal models of heart failure with associated MR. In this article, we report results of a "first-in-human" study of temporary placement of the PMAD device. The aim of this study was to demonstrate the feasibility and safety of temporary deployment of this device in patients with functional MR in association with heart failure. Five patients undergoing scheduled coronary angiography with heart failure and functional MR (mean age 52 +/- 9 [SD] years) were recruited, and four had anatomy suitable for deployment of the device. Transthoracic echocardiography and coronary angiography were performed before and after temporary placement and tensioning of the PMAD via the right internal jugular vein. Temporary deployment of the device resulted in a significant reduction in the septal-lateral mitral annular dimension from 35.5 +/- 4.7 to 32.2 +/- 4.6 mm (P = 0.02), with evidence of a reduction in the MR color Doppler area from 98.3 +/- 43.6 to 83.3 +/- 35.1 mm(2) (P = 0.09). There were no complications. This first-in-human study of a novel device for percutaneous treatment of functional MR has shown that temporary placement of this device in the coronary sinus/great cardiac vein of patients with heart failure and MR is feasible and safe. Evidence of temporary reduction in MR and a reduction in mitral annular area indicate promise for device effectiveness in chronic implantation.

Percutaneous Mitral Annular Reduction Provides Continued Benefit in an Ovine Model of Dilated Cardiomyopathy

Functional mitral valve regurgitation plays a key role in the symptomatic severity and progression of heart failure. In an ovine model of dilated cardiomyopathy, we examined the chronic functional consequences of mitral regurgitation reduction using a recently developed novel percutaneous mitral annular reduction (PMAR) device. Fourteen adult sheep were paced right ventricularly at 180 to 190 bpm for 5 weeks, leading to the development of moderate mitral valve regurgitation. After echocardiographic, hemodynamic, and neurohormonal analysis, 9 animals underwent PMAR. All animals were subsequently paced for another 28 days, and a final echocardiographic and hemodynamic study was conducted. Animals that had undergone PMAR showed significantly increased negative and positive dP/dt, whereas pulmonary capillary wedge pressure and mitral valve regurgitation were significantly reduced compared with those at device implant despite continued pacing. In conjunction, significant improvements in plasma norepinephrine and brain natriuretic peptide were apparent. The application of PMAR in animals with pacing-induced dilated cardiomyopathy and functional mitral valve regurgitation resulted in continued improvements in hemodynamic and neurohormonal parameters.

Atrial contraction and mitral annular dynamics during acute left atrial and ventricular ischemia in sheep.

In six sheep, radiopaque markers were placed on the left ventricle (LV), the mitral annulus, the left atrium (LA), and the central edge of both mitral leaflets to investigate the effects of acute LV ischemia on atrial contraction, mitral annular area (MAA), and mitral regurgitation (MR). Animals were studied with biplane videofluoroscopy and transesophageal echocardiography before and during balloon occlusion of the left anterior descending (LAD), distal circumflex (dLCX), and proximal circumflex (pLCX) coronary arteries. MAA and LA area were calculated from the corresponding markers. LAD occlusion did not alter LA area reduction or presystolic MAA reduction, whereas dLCX occlusion resulted in a mild decrease in the former with no change in the latter. Neither occlusion resulted in MR. pLCX occlusion, however, significantly decreased LA area and presystolic MAA reduction and resulted in increased end-diastolic MAA, delayed valve closure from end diastole, and MR. Decreased atrial contractile function, as observed during acute posterolateral ischemia, is linked to diminished presystolic mitral annular reduction, a larger mitral annular size at end diastole, and MR.