Prehabilitation for Cardiac Surgery in Patients With Reduced Exercise Tolerance

Among patients awaiting cardiac surgery, a significant proportion are patients with severe angina, heart failure (HF) and peripheral atherosclerosis. These factors are predictors of an unfavorable near and long-term prognosis after open cardiac surgery. It is known that the restriction of motor activity in patients with peripheral atherosclerosis and HF leads to loss of muscle mass, as well as to a decrease in its strength and endurance: secondary (disuse) sarcopenia is formed. In patients with peripheral atherosclerosis and HF, the low functional status of skeletal muscles is associated with a poor prognosis, regardless of gender, age, and concomitant coronary artery disease. A number of studies have shown that the deterioration of muscle status before abdominal, orthopedic and vascular surgery interferes with the close results of surgery, increases the number of complications, the length of ICU and in-hospital stay. Thus, sarcopenia serves as an additional factor worsening the prognosis. Therefore, efforts aimed at improving the functional status in patients planning an open cardiosurgical surgery seem to be very justified.

Standard preoperative management of patients includes the identification and correction of comorbidities and the optimal medical treatment. The idea of "rehabilitation" means an additional improvement in the functional capabilities of patients awaiting surgery. Prevention includes outpatient outreach and educational work by nurses, as well as preoperative physical exercises. For this, multi-level training is used: respiratory exercises for the patients with the most severe illness, free movements of the limbs without load, or bike or treadmill training with increasing load for tolerable patients.

However, adequate physical rehabilitation is difficult particularly on an outpatient basis. Low adherence is due in part to inadequate strength and inability to tolerate or sustain even low levels of activity due to angina, chronic lower limb ischemia and heart failure symptoms.

In this study, the investigators propose to use neuromuscular electrical stimulation (NMES) to assist patient initiation of quadriceps strengthening in order to progressively increase low exercise tolerance.


Eligibility Criteria:
Inclusion Criteria:

* Patients awaiting for elective cardiovascular procedure (CABG, valvular or thoracic aorta) unable to walk more than 300 meters during six-minuite walking test due to angina, dyspnea or limb ischemia
* no weakness of lower limbs
* stable hemodynamic, already received standard treatment based on patient condition
* able to follow protocol procedures
* assigned the informed consent
* do not regularly exercise (10 minutes or more a day of exercise most days of the week for the past week).

Exclusion Criteria:

* urgent indications for surgery or counterindication for elective operation
* already receive NMES at femoris area in last 6 weeks before admission
* Patients, who have undertaken cardiac rehab within the 12 months prior to enrollment
* Cognitive, orthopedic or neurological disorders or other impairment which prevents accurate application of intervention or inability to provide informed consent
* End Stage Renal Disease
* Uncontrolled arrhythmia's or 3rd degree AV heart block
* Those with wounds over area of proper placement of electrodes