Try our beta test site
IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more...

Surgical Sympathetic Blockade in Heart Failure (SymBlock)

This study has been completed.
Information provided by:
University of Sao Paulo Identifier:
First received: October 18, 2010
Last updated: October 19, 2010
Last verified: October 2010
The investigators sought to evaluate the feasibility and safety of surgical sympathetic blockade in systolic heart failure patients and secondary to assess its cardiovascular consequences.

Condition Intervention Phase
Systolic Heart Failure
Beta-blockers Intolerance
Beta-blockers Resistance
Procedure: Left cervico-thoracic sympathetic blockade
Phase 1

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Left Cervico-Thoracic Sympathetic Blockade by Clipping in Systolic Heart Failure: A Randomised Controlled Trial

Resource links provided by NLM:

Further study details as provided by University of Sao Paulo:

Primary Outcome Measures:
  • Perioperative mortality and morbidity [ Time Frame: 30 days after operation ]

    Study interruption criteria:

    • death attributable to surgical procedure;
    • cardiogenic shock attributable to surgical procedure;
    • worsening of heart failure symptoms attributable to surgical procedure;
    • Horner's syndrome
    • hypotension or bradiarrhythmia attributable to surgical procedure

Secondary Outcome Measures:
  • Cardiovascular effects [ Time Frame: 6 months ]
    • left ventricle ejection fraction (echo and gated blood pool)
    • end left ventricle diastolic diameter
    • mean heart rate
    • heart rate variability
    • New York Heart Association functional class
    • Minesotta Living with Heart Failure Questionnaire Score
    • peak oxygen consumption
    • walked distance in 6 minute walking test
    • BNP
    • 123-I-Metaiodobenzylguanidine (late heart/mediastinum ratio)
    • sympathetic peripheral nerve activity (microneurography)
    • baroreflex parameters (low and high frequency)

Enrollment: 15
Study Start Date: December 2006
Study Completion Date: July 2010
Primary Completion Date: November 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Surgery Procedure: Left cervico-thoracic sympathetic blockade
Left cervico-thoracic sympathetic blockade by videothoracoscopic clipping under general anesthesia and single-lumen orotracheal intubation in semi-sitting position.
No Intervention: Control


Ages Eligible for Study:   18 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • chronic heart failure (at least 1 month of symptoms onset)
  • NYHA functional class II or III
  • LV ejection fraction 40% or lower
  • resting heart rate higher than 65 bpm
  • either maximum beta-blocker therapy according to guidelines or no beta-blocker use for intolerance.

Exclusion Criteria:

  • NYHA functional class I or IV
  • cardiogenic shock
  • resting heart rate ≤ 65 bpm
  • systolic blood pressure < 90 mmHg
  • sustained ventricular tachycardia
  • eligibility to other surgical procedures
  • procedure-limiting comorbidity
  • presence of ICD or pacemaker
  • valvar, chagasic or congenital cardiomyopathy
  • age > 70 years
  • patient refusal
  • contra-indication to videothoracoscopy
  • decompensated thyroid disease
  • atrial fibrillation or flutter
  • active infection
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01224899

Heart Institute (InCor) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo
São Paulo, SP, Brazil, 05403000
Sponsors and Collaborators
University of Sao Paulo
Study Chair: Edimar A Bocchi, MD Heart Institute (InCor) HC FMUSP
Principal Investigator: Paulo M Pego-Fernandes, MD Heart Institute (InCor) HC FMUSP
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Paulo Manuel Pego Fernandes, Heart Institute (InCor) HC FMUSP Identifier: NCT01224899     History of Changes
Other Study ID Numbers: SymBlock Trial
Study First Received: October 18, 2010
Last Updated: October 19, 2010

Keywords provided by University of Sao Paulo:
Heart Failure
Sympathetic Nervous System
Adrenergic beta-Antagonists
Ventricular Dysfunction, Left

Additional relevant MeSH terms:
Heart Failure
Heart Failure, Systolic
Heart Diseases
Cardiovascular Diseases processed this record on April 25, 2017