Clinical Trials Logo
NCT number NCT03189368
Study type Observational
Source National and Kapodistrian University of Athens
Contact Polychronis Dilaveris, MD
Phone 6944681361
Email hrodil1@yahoo.com
Status Not yet recruiting
Phase N/A
Start date July 1, 2017
Completion date November 1, 2020

Clinical Trial Summary

To perform a comparative study of multi-site left ventricular pacing and cardiac resynchronization therapy effects on ventriculoarterial coupling and energy efficiency of the failing heart


Clinical Trial Description

Given that the main function of the cardiovascular system is to provide sufficient blood supply to tissues in order to ensure their normal and effective function, combined with the most efficient possible use of energy produced by ATP degradation, there has been a keen interest in elucidating the interplay between heart and vessels, critically affecting both.

In order to achieve these goals, it is thought that in healthy humans the cardiovascular system as a unity operates at a unique combination of parameters (arterial elastance, heart rate and left ventricular end systolic elastance) so as to:

1. Maximize stroke work (SW) for a given left ventricular contractility. This is related to the fact that adequate tissue perfusion is dependent both on stroke volume and on pressure and in fluid dynamics W=∆P×∆V (thus maximizing SW leads to optimal perfusion), OR

2. Optimize energy efficiency of the heart, in terms of energy transferred to the arterial bed to total mechanical energy.

Ventriculoarterial coupling (VAC) is a composite parameter, defined as the ratio of arterial elastance (Ea) to end systolic left ventricular elastance (Ees). Thus: VAC=Ea/Ees . It is a fundamental property of the cardiovascular system, integrating and assessing the interaction of all individual parameters of the ventricle (pump) and the arterial tree (afterload). Furthermore, VAC may assess both whether SW produced is maximal for a given contractility of the left ventricle (condition for maximization: VAC=1) and whether mechanical efficiency of the ventricle is optimal (optimization condition: VAC=0.5-0.7). Consequently, simultaneous optimization is not possible, and the cardiovascular system operates either at maximal output (as in healthy individuals at rest) or at optimal efficiency (healthy individuals at exercise). Multi-site pacing (MSP) of the left ventricle is a recently introduced technique with excellent studies' findings concerning echocardiographic parameters of ventricular function. Recently, the MultiPoint Pacing (MPP) IDE study showed that a specific choice of electrical dipole for the first left ventricular pulse and a close to simultaneous application of the two left ventricular pulses achieves a very high percent of clinical response (87%), with excellent patient safety. Subsequent studies confirmed these findings, reporting even higher NYHA response rates (95% vs 78% for conventional cardiac resynchronization therapy - CRT).

The underlying rationale lies in the better approximation of the normal sequence of left ventricular activation, through use of two, instead of a single, pulses. According to trial results, one can achieve, compared to conventional CRT, improved coordination between left ventricular segments, improved cardiac output and, possibly, tissue perfusion, and potentially reduction of arrhythmia propensity (mechanism similar to that of CRT). Thus, it would be interesting to study whether these can be independently confirmed by changes in VAC values. In heart failure, VAC values increase considerably due to increases in Ea as a result of the feedback loop regarding pressure (but not volume) maintenance. As a consequence, any reduction would move them closed to both 1 and the 0.5-0.7 area, yielding improvement in both SW maximization and efficiency optimization.

However, there are objective difficulties in achieving lege artis MSP (according to MPP-IDE study standards) given that two prerequisites must be met: 1. Interpolar distance for the first left ventricular pulse >30mm (i.e. non-sequential poles used), 2. Nearly simultaneous (Δt=5msec) left ventricular pulses and 3. Threshold of ≤3.5V@0.5msec.

Moreover, the first pulse should, ideally, be directed to the most delayed, compared to the normal activation sequence, viable myocardial segment, a feat not always possible due to electrode placing constraints. Obviously, presence of scar could alter the course and shape of the activation front and thus diminish its effects (similar to issues already discussed in the case of CRT).

Objective:

To perform a comparative study of multi-site left ventricular pacing and cardiac resynchronization therapy effects on ventriculoarterial coupling and energy efficiency of the failing heart

Hypothesis:

VAC values are improved (shift closer to unity/0.5-0.7 area) and work/efficiency increase with patients on MSP as compared to CRT pacing.


Study Design


Related Conditions & MeSH terms


See also
  Status Clinical Trial Phase
Withdrawn NCT03091998 - Subcu Administration of CD-NP in Heart Failure Patients With Left Ventricular Assist Device Support Phase 1
Recruiting NCT02275819 - Exercise Training in Heart Failure: Changes in Cardiac Structure and Function N/A
Not yet recruiting NCT03003780 - Mindful Steps: Promoting Physical Activity N/A
Not yet recruiting NCT02922036 - Stimulation Of the Left Ventricular Endocardium for Cardiac Resynchronization Therapy in Non-Responders and Previously Untreatable Patients Phase 3
Not yet recruiting NCT03228030 - Thiamine Supplementation in Heart Failure: a Pilot Randomized Controlled Crossover Trial Phase 3
Not yet recruiting NCT03170466 - Primary Palliative Care in Heart Failure: A Pilot Trial N/A
Not yet recruiting NCT02784912 - Biomarkers in Risk Stratification of Sustainted Ventricular Tachycardia or Electrical Storm After Ablation N/A
Not yet recruiting NCT03245281 - LINQ for impEdance meAsuremeNt While Off From HF Medication Study Phase 4
Recruiting NCT03013270 - Aerobic, Resistance, Inspiratory Training Outcomes in Heart Failure N/A
Recruiting NCT02713126 - Inorganic Nitrite to Amplify the Benefits and Tolerability of Exercise Training in HFpEF (INABLE-Training) Phase 2
Recruiting NCT02914665 - A Phase 2 Study to Evaluate the Cardiac and Renal Effects of Short Term Treatment With Elamipretide in Patients Hospitalized With Congestion Due to Heart Failure Phase 2
Recruiting NCT02911493 - Reducing Sedentary Time in Patients With Heart Failure N/A
Recruiting NCT02823795 - The Supporting Patient Activation in Transition to Home Intervention N/A
Recruiting NCT02921607 - Development of Scalable New Model(s) Focused on Care Co-ordination and Care Provision for Medically Complex, Co-morbid Chronic Disease Patient Segments Focusing on Heart Failure N/A
Recruiting NCT03071952 - Assessment of AAIR Pacing Treatment for Heart Failure Patients With Chronotropic Incompetence N/A
Active, not recruiting NCT02922478 - Role of Comorbidities in Chronic Heart Failure Study N/A
Withdrawn NCT02624960 - Safety and Performance of the AccuCinch® System N/A
Not yet recruiting NCT02877914 - China PEACE 5r-HF Study N/A
Not yet recruiting NCT02821065 - Telehealth for Emergency-Community Continuity of Care Connectivity Via Home-Telemonitoring N/A
Not yet recruiting NCT02903940 - The Application of Negative Atrioventricular Hysteresis in Cardiac Resynchronization Therapy N/A