Surgical alternatives to transplantation and assist devices in the treatment of heart failure

Systematic Reductive Annuloplasty of the Mitral and Tricuspid Valves in Patients With End-Stage Ischemic Dilated Cardiomyopathy

OBJECTIVE

Patients with ischemic dilated cardiomyopathy exhibit extensive remodeling of the left ventricle, annular dilation, and significant mitral and tricuspid regurgitation. These changes increase per operative morbidity and mortality, and emphasize patient candidacy for heart transplantation. The aim of this study is to show immediate and long-term results after reductive annuloplasty of double (mitral and tricuspid) orifices, performed at the time of coronary artery bypass grafting, as an alternative to heart transplantation.

METHODS

There were 226 consecutive patients (205 males, 21 females) with ischemic dilated cardiomyopathy, mean ejection fraction below 30% [(26.6 +/- 3.1)%], and mean left ventricle end-diastolic internal diameter greater than 7.0 cm (7.3 +/- 0.3 cm). In addition to myocardial revascularization, Carpentier's mitral annuloplasty and posterior semicircular reductive annuloplasty were performed in 37 and 189 patients, respectively. In all 226 patients, a modified De Vega's tricuspid annuloplasty was performed.

RESULTS

Postoperative 30-day mortality was 7.5% (17 patients). Survival rates after 5 and 10 years were (61.5 +/- 4.0)% and (38.05 +/- 8.0)%, respectively.

CONCLUSION

Reductive annuloplasty of mitral and tricuspid orifices performed at the time of myocardial revascularization could be beneficial in selective patients with ischemic dilated cardiomyopathy. Results indicate that this method should not be recognized as a valve repair, but ventricular repair procedure also.

New surgical therapies for heart failure

A growing number of patients present with heart failure. Some of them may qualify for surgical correction of their cardiac condition. Since heart transplantation will always be available to only a small number of patients, several new surgical techniques have been developed for approval in heart failure patients. Classic interventions such as revascularization, valve repair, or valve replacement have been improved and modified to meet the need of heart failure patients. Several of these techniques are currently under investigation in large clinical trials. These trials will definitely have an impact on the development of surgical treatment of patients with heart failure.

Reverse remodeling and improved regional function after repair of left ventricular aneurysm

BACKGROUND

Changes in regional left ventricular mechanics after anteroapical aneurysm repair in human subjects can be studied noninvasively by means of magnetic resonance tagging. We hypothesized that left ventricular intramyocardial function would improve throughout the left ventricle after repair.

METHODS

We studied 6 male patients with a left ventricular anteroapical aneurysm (mean age +/- SD, 63 +/- 5 years) using magnetic resonance tagging 3 +/- 1 weeks before and 6 +/- 1 weeks after aneurysm repair, coronary artery bypass grafting, and mitral valve repair (n = 2). Breath-hold tagged imaging spanned the left ventricle in the short axis from apex to base. Left ventricular mass, end-diastolic and end-systolic volume, and ejection fraction were measured. Two-dimensional strain analysis was applied; averaged for the apical, middle, and basal left ventricle and the whole left ventricle; and expressed as greatest lengthening (similar to wall thickening), greatest shortening, and angular deviation of the lengthening strain from the radial direction.

RESULTS

After aneurysm repair, left ventricular mass decreased from 373 +/- 27 to 333 +/- 25 g (P <.05), end-diastolic volume from 212 +/- 22 to 168 +/- 18 mL (P <.005), and end-systolic volume from 188 +/- 26 to 113 +/- 18 mL (P <.005); ejection fraction improved from 13% +/- 4% to 23% +/- 4% (P <.005). For the whole left ventricle, lengthening strain increased from before to after the operation (8% +/- 1% to 10% +/- 1%, P <.01). Most of the improved lengthening occurred at the middle left ventricle (8% +/- 1% to 11% +/- 1%, P <.01), in the base (8% +/- 1% to 10% +/- 1%, P <.05), and in the inferior wall (9% +/- 1% to 12% +/- 1%, P <.05). Lengthening tended to become more radially oriented, decreasing from 31 degrees +/- 3 degrees to 27 degrees +/- 3 degrees (P =.10). Shortening strain did not change (10% +/- 1% to 11% +/- 1%, P = not significant).

CONCLUSIONS

Left ventricular aneurysm repair is associated with reverse remodeling and an improvement in the extent and orientation of intramyocardial function, especially at the middle and basal left ventricle and inferior wall.

Mitral ring annuloplasty: an incomplete correction of functional mitral regurgitation associated with left ventricular remodeling

Functional mitral regurgitation (FMR) occurs commonly in patients undergoing left ventricular (LV) remodeling. It is ubiquitous in patients referred to cardiac transplantation for LV systolic dysfunction and predicts a poor prognosis. The LV remodeling that is responsible for FMR is well understood and involves regional LV dysfunction Mitral annular dilatation is present in patients with idiopathic dilated cardiomyopathy but most often absent in patients with ischemic cardiomyopathy. Nonrandomized observations indicate that implantation of a mitral undersized flexible mitral ring reduces the amount of FMR, reverses LV remodeling, and improves symptoms in patients with end-stage cardiomyopathy and severe FMR. Whether a surgical procedure that does not correct the major LV alterations leading to FMR can have long-lasting effects on the amount of FMR and the reversal of LV remodeling remains to be demonstrated in randomized trials.