Prospective Minnesota Study of ECHO Tissue Doppler Imaging in Cardiac Resynchronization Therapy

Inclusion Criteria:

Moderate or severe heart failure defined as NYHA class III-IV despite optimal pharmacological heart failure therapy.

Stable Heart failure as defined as not hospitalized within the last month. A 12 lead electrocardiogram (ECG) obtained no more than 90 days prior to enrollment documenting a sinus rate >50bpm, QRS duration >120ms and PR interval> 150ms Ejection Fraction <35% documented within the last 6 months by one of the following methods: echo ( standard or TEE) LV gram, or MUGA Clinically indicated to receive CRT Ability to complete all the study visits including geographic stability

Exclusion criteria:

Serum creatinine >3.5 Have or had a Myocardial infarct, unstable angina, percutaneous coronary intervention or coronary artery bypass graft during the preceding 30 days prior to enrollment.

Have had previous cardiac resynchronization therapy, a coronary venous pace/sense lead or attempted LV lead placement.

Dyspnea believed by the physician to be primarily related to lung disease. Have an atrial tachyarrhythmia that is permanent ( ie does not terminate spontaneously and cannot be terminated with medical intervention)or persistent (can be terminated with medical intervention but does not terminate spontaneously)within 90 days prior to enrollment Poor sinus node function that MD predicts will require >70% atrial pacing. Inability to perform the six minute walk. Life expectancy of less than 6 months due to other medical conditions or expected to undergo heart transplant within the next 6 months.

Have a mechanical tricuspid heart valve. Hypertrophic obstructive cardiomyopathy. Patients with a hypersensitivity to a 0.7mg nominal dose of dexamethasone. Surgically uncorrected primary valvular heart disease. Patients who are currently enrolled in another investigational study that would directly impact the treatment or outcome of the current study.

Patients who are younger than 18 years of age, pregnant, or who are mentally incompetent and cannot sign a patient informed consent.

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