left ventricular synchronous versus sequential multispot pacing for cardiac resynchronization therapy (crt)

Conditions: Heart Failure

Summary: the synseq study intends to assess the positive left ventricular dp/dt max achieved by multispot lv pacing (either simultaneously or sequentially) in comparison to the response achieved by the current (standard) biv pacing configuration in patients indicated/recommended for cardiac resynchronization therapy.

the following pacing configurations will be evaluated. biventricular pacing (biv): pacing will be performed on one lv electrode pair, (at 3 different longitudinal locations), and on the tip of the rv-lead. in total, three different pacing biv settings will be evaluated. configuration 1: rv + lv lateral apex, configuration 2: rv + lv lateral mid, configuration 3: rv + lv lateral base (reference: standard crt) multispot simultaneous lv-ventricular pacing (multispot-syn): pacing will be performed on 3 electrodes on the lv wall, placed at different longitudinal locations, and on the tip of the rv-lead simultaneously. configuration 4: rv + lv lateral apex + lv lateral mid + lv lateral base multispot sequential lv-ventricular pacing (multispot-seq): 3 electrodes on the lv wall will be paced sequentially. the rv electrode will be paced simultaneously with last paced lv electrode.the timing-sequence and the amount of spots will depend on the electrical delays measured during the experiments. configuration 5: lv lateral apex =\> lv lateral mid =\> lv lateral base + rv

Eligibility criteria:
inclusion criteria: * subject is indicated or recommended for crt-p or crt-d device according to current applicable esc/aha guidelines * subject is in sinus rhythm * subject receives optimal heart failure oral medical therapy * subject is willing to sign the informed consent form * subject is 18 years or older exclusion criteria: * subject has permanent atrial fibrillation/flutter or tachycardia * subject has pure right bundle branch block (= no additional left ventricular conduction delays) * subject has left bundle branch block and qrs-duration of \> 150 ms and no sign of myocardial scar indicated by late gadolinium enhancement mri * subject experienced recent myocardial infarction, within 40 days prior to enrollment * subject underwent valve surgery, within 90 days prior to enrollment * subject is post heart transplantation, or is actively listed on the transplantation list * subject is implanted with a left ventricular assist device * subject has severe renal disease (up to physicians discretion) * subject is on continuous or uninterrupted infusion (inotropic) therapy for heart failure (≥ 2 stable infusions per week) * subject has severe aortic stenosis (with a valve area of \<1.0 cm2 or significant valve disease expected to be operated within study period) * subject has complex and uncorrected congenital heart disease * subject has a mechanical heart valve * pregnant or breastfeeding women, or women of child bearing potential and who are not on a reliable form of birth control * subject is enrolled in another study that could confound the results of this study, without documented pre-approval from medtronic study manager