In inoperable patients with severe aortic stenosis, balloon valvuloplasty can enhance survival, function, and quality of life (QoL)—at least in the short term—according to data from the PARTNER trial published in the February 2015 issue of JACC: Cardiovascular Interventions. In addition to being palliative, the authors say, the procedure may serve as a bridge to surgical or transcatheter valve replacement in patients with temporary contraindications.

In the PARTNER Cohort B study, inoperable patients were randomized to TAVR (n = 179) or standard treatment (n = 179). For the current post hoc analysis, a team led by E. Murat Tuzcu, MD, of the Cleveland Clinic (Cleveland, OH), looked at 140 patients (mean age 83.1 years; 50% male) who received standard treatment and had not undergone valvuloplasty before enrollment. Of this cohort, 102 patients had valvuloplasty within 30 days after randomization (median 3 days), at the physician’s discretion.

Valvuloplasty patients had more severe congestive heart failure symptoms and a higher logistic EuroSCORE than those who did not undergo the procedure. However, there were no differences between the groups in Society of Thoracic Surgeons (STS) score, echocardiographic characteristics, or QoL parameters.

Valvuloplasty improved mean gradient (-13.2 ± 13.5 mm Hg; P < .0001) and aortic valve area (0.2 ± 03 cm²; P < .0001) over baseline. However, repeat valvuloplasty (29 patients underwent a second procedure, 7 a third, and 2 a fourth) yielded negligible or no hemodynamic gains.

After the 189 valvuloplasties performed during the trial, there were 8 deaths and 2 strokes within 30 days. There was no change in the magnitude of aortic regurgitation after the procedure.

Temporary Improvements in Functional Status, QoL

Valvuloplasty was associated with improvements in heart failure symptoms manifested by fewer patients in NYHA functional class III or IV at 3 and 6 months. In addition, several QoL parameters were better at 30 days and 6 months after valvuloplasty, although the effect was lost by 12 months.

Survival was higher in treated vs untreated patients (88.2% vs 73.0%) at 3 months but similar at 6 months (both about 74%).

Several factors predicted higher mortality, including:

• Stroke/TIA within the past 6-12 months
• Previous pacemaker implantation
• Higher NYHA functional class
• LVEF < 35%
• Baseline A-fib
• Previous aortic valvuloplasty
• History of arrhythmia
• STS score > 11

In 11 patients (6.1%) from the inoperable cohort—of whom10 had a valvuloplasty and 1 did not—overall clinical status improved such that they were able to undergo surgical valve replacement. Only half of them, however, survived another year after surgery.   

 A Bridge to Replacement

“Our study may be the first, and possibly the last, study in which inoperable high-risk medically managed patients with [aortic stenosis] were carefully studied without aortic replacement in a randomized fashion,” the authors observe. They add that the results, derived in the setting of contemporary valvuloplasty in carefully selected patients, may serve as a benchmark for future trials of new interventions.

In clinical practice, valvuloplasty serves mainly to bridge high-risk patients to definitive surgical or transcatheter valve replacement, Dr. Tuzcu and colleagues say. They explain that bridging may be required due to temporary contraindications to replacement (eg, sepsis or severe debilitation), other significant cardiac lesions where the relative contribution of aortic stenosis to heart failure remains questionable, or the presence of severe noncardiac comorbidities that make it difficult to tease out the role of stenosis in presenting symptoms.

Valvuloplasty can also be used for palliation when replacement is not feasible because of serious comorbidities, the investigators say. However, the benefits of such a strategy are short-lived.

The authors caution that because all patients were screened and approved for possible randomization to TAVR, the results cannot be extrapolated to subjects who were excluded from the trial.

Benefits Overestimated?

“The benefits of balloon aortic valvuloplasty tend to be overestimated and the risks understated,” asserted Howard C. Herrmann, MD, of the Hospital of the University of Pennsylvania (Philadelphia, PA), in an email with TCTMD.

He noted that the study likely has “significant selection bias,” with only about 20% of patients in the overall cohort not receiving valvuloplasty.

While acknowledging that the procedure may provide short-term relief—which has been demonstrated in many previous studies—Dr. Herrmann said he was skeptical of the reported small mortality benefit at 3 months. In fact, the treated and untreated groups were “not compared statistically due to the limitations of the patient population, timing, and selection for [valvuloplasty],” he commented.

Dr. Herrmann called the postvalvuloplasty improvement that apparently enabled surgery in a small percentage of patients “intriguing” yet cautioned that “the reconsideration may have been due to other reasons or might have occurred anyway.”

But according to coauthor Ted Feldman, MD, of Evanston Hospital (Evanston, IL), patients with congestive heart failure are often more responsive to medical therapy after valvuloplasty. In addition, he told TCTMD in an email, the procedure may be used in certain cases—such as when LVEF is very low or lung disease is a major cause of symptoms—to see if a patient improves with aortic gradient reduction, serving as a test of whether TAVR might provide a similar, more lasting effect.

Dr. Feldman added that patients may react differently to the small risk and limited durability of valvuloplasty; while some welcome repeat procedures roughly once a year to help relieve symptoms, others opt to forgo the procedure entirely in favor of “comfort care.”

Note: Coauthors Martin B. Leon, MD, and Jeffrey W. Moses, MD, are faculty members of the Cardiovascular Research Foundation, which owns and operates TCTMD.

Source:
Kapadia S, Stewart WJ, Anderson WN, et al. Outcomes of inoperable symptomatic aortic stenosis patients not undergoing aortic valve replacement: insight into the impact of balloon aortic valvuloplasty from the PARTNER trial (Placement of AoRtic TraNscatherER valve trial). J Am Coll Cardiol Intv. 2015;8:324-333.

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