Quantitative Assessment of Hypertrophic Obstructive Cardiomyopathy With Intraoperative Three-dimensional Transesophageal Echocardiography Under Provocative Dobutamine Stress Test

NCT05025644 | Unknown Phase 4

• 1 other identifier: 16-5412
• Study Type: interventional
• Target: 60
• Locations: 0 countries
• Sites: N/A

Brief Summary

The objectives of this study are to determine if the left ventricle outflow tract (LVOT) gradients may be reproduced with dobutamine (DBT) provocation test in obstructive HCM patients under general anesthesia and to analyze the change in anatomic LVOT area and pressure gradients (PG) before and after septal myectomy. If the DBT stress test can reproduce preoperative gradients in HCM patients during septal myectomy surgery, surgeons will have the opportunity to assess the quality of the surgical procedure depending on the obtained gradients with DBT stress test after surgery when gradients can't be reproduced during general anesthesia after myectomy, and decide if further myectomy is required, saving a re-operation on the patient in the future.

Conditions

Hypertrophic Obstructive Cardiomyopathy

Keywords

Transesophageal Echocardiography; Dobutamine Stress test

Outcome Measures

Primary Outcomes (1)

• Analyze if TEE immediate post-myectomy LVOT gradients, may be reproduced with provocation dobutamine test in HOCM patients, when compared to TTE LVOT gradients performed within 6 months post-myectomy, to prove septal myectomy efficacy.

  The preoperative gradients obtained by TTE, with and without stress test, within 6 months pre-myectomy, will be compared with the intraoperative TEE pre-myectomy gradients at baseline (before and after DBT stress test). The post-myectomy TEE gradients (before and after DBT stress test), will be compared with the follow up TTE gradients with and without stress test, performed within 6 months post-myectomy, to assess short term outcomes.

  Pre-operative up to 6 months, Immediate Intra-operative Pre-myectomy, Immediate Intra-operative Post-myectomy and Post-operative up to 6 months

Study Arms (2)

Preoperative Transesophageal Echocardiogram (TEE) PG under anesthesia <50mmHg (Group A)

EXPERIMENTAL

* Pre-cardiopulmonary bypass (CPB) (pre-myectomy) echocardiographic parameters: PG under DBT stress test at 5, 10, 15 and 20 mcg/kg/min or until a PG ≥ 50mmHg is achieved, will be recorded. * Post-CPB (post-myectomy) echocardiographic parameters: PG at DBT peak dose (DBT-pd) will be recorded. If LVOT PG post myectomy are \>16 mmHg, the surgeon will be advised, for surgical management considerations.

Drug: Pre and post-CPB Drug: Dobutamine Hydrochloride

Preoperative PG under anesthesia ≥ 50mmHg (Group B)

EXPERIMENTAL

* Pre-cardiopulmonary bypass (CPB) (pre-myectomy) echocardiographic parameters: PG without DBT stress test will be recorded. * Post-CPB (post-myectomy) echocardiographic parameters: PG at 5, 10, 15, 20 mcg/kg/min DBT stress test or until the postoperative provocable PG is \>16 mmHg will be recorded.

Drug: Post-CPB Drug: Dobutamine Hydrochloride

Interventions

Pre and post-CPB Drug: Dobutamine Hydrochloride DRUG

* Pre-CPB provocation test with DBT stress test will be started (starting at 5 mcg/kg/min, increasing every 3 min, to 10, 15 and 20 mcg/kg/min) until a PG ≥ 50mmHg is achieved (DBT peak dose). The DBT peak dose (DBT-pd) will be recorded. * Post-CPB provocation test at the DBT-pd achieved preoperatively.

Also known as: Transthoracic or 2D Echocardiogram, Transesophageal Echocardiogram (TEE)

Preoperative Transesophageal Echocardiogram (TEE) PG under anesthesia <50mmHg (Group A)

Post-CPB Drug: Dobutamine Hydrochloride DRUG

* Pre-CPB no intervention will be required. * Post-CPB provocation test with DBT stress test will be started (starting at 5 mcg/kg/min, increasing every 3 min, to 10, 15 and 20 mcg/kg/min) or until postoperative provocable PG is \>16 mmHg.

Also known as: Transthoracic or 2D Echocardiogram, Transesophageal Echocardiogram (TEE)

Preoperative PG under anesthesia ≥ 50mmHg (Group B)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• HOCM refractory to medical treatment with symptoms like syncope, angina or NYHA functional classes III and IV, with a resting gradient or provocable gradient equal or greater than 50 mmHg, requiring surgical intervention.
• Absence of other cardiac or systemic diseases capable of producing hypertrophy.
• Sinus rhythm.

You may not qualify if:

• Patient refusal.
• Patient unable to give consent.
• TEE contraindication.
• Different rhythm than sinus.
• Other systemic diseases capable of producing hypertrophy.
• Severe Aortic or coronary artery pathology.

Sponsors & Collaborators

• University Health Network, Toronto: lead

MeSH Terms

Conditions

Cardiomyopathy, Hypertrophic

Interventions

Lead

Condition Hierarchy (Ancestors)

Cardiomyopathies; Heart Diseases; Cardiovascular Diseases; Aortic Stenosis, Subvalvular; Aortic Valve Stenosis; Aortic Valve Disease; Heart Valve Diseases

Intervention Hierarchy (Ancestors)

Metals, Heavy; Elements; Inorganic Chemicals; Metals

Study Officials

• Jacobo Moreno Garijo, MD

  Sunnybrook Health Science Centre

  PRINCIPAL INVESTIGATOR

• Azad Mashari, MD

  University Health Network, Toronto

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Azad Mashari, MD

CONTACT

(416) 340-4800; azad.mashari@uhn.ca

Jo Carroll

CONTACT

416 340-4800; jo.carroll@uhn.ca

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: This is a monocentric Phase IV prospective study that will be conducted on patients undergoing surgical myectomy treatment for HOCM, at Toronto General Hospital, to assess if LVOT gradients may be reproduced with dobutamine provocation test in HOCM patients under general anesthesia. The participants in the study will require a standard 2D echocardiography within 6 months pre and post-surgery. Intraoperatively, the patients will be divided into two groups, one with preoperative PG under anesthesia \<50mmHg (Group A), and one with preoperative PG under anesthesia ≥ 50mmHg (Group B).

Study Record Dates

• First Submitted: August 11, 2021
• First Posted: August 27, 2021
• Study Start: March 1, 2023
• Primary Completion: August 1, 2024
• Study Completion: November 1, 2024
• Last Updated: November 8, 2022

Record last verified: 2022-11