# Evaluation of Fiberoptic Confocal Microscopy for Pediatric Cardiac Surgery

> **NIH NIH R01** · BOSTON CHILDREN'S HOSPITAL · 2020 · $492,949

## Abstract

PROJECT SUMMARY/ABSTRACT
Our long-term aim is to establish real-time fiber-optics confocal microscopy (FCM) as an intraoperative imaging
modality in cardiac surgery, particularly in pediatric open-heart surgery. A major risk of cardiac surgery is
damage to the conduction system, which is responsible for initiating electrical signals, conducting them rapidly
through the heart and synchronizing mechanical activation. Damage to the conduction system is associated
with significant morbidity and (in extreme cases) necessitates costly pacemaker insertion. Despite individual
variations in the conduction system, discrimination of this tissue during surgery is currently limited to the visual
identification of anatomical landmarks. Our preliminary studies on several animal models and human tissue
indicate that microscopic images of cardiac tissue provide sufficient information for visual discrimination of
tissue of the conduction system and working myocardium. Furthermore, we identified automated methods for
tissue discrimination based on quantitative texture analysis of microscopic images. In this project, we will
further develop this real-time imaging modality and analysis methods so that clinicians can use the approach
during surgical procedures to avoid damage to tissue of the cardiac conduction system. We will evaluate our
approaches in explanted human hearts, in-vivo ovine model of neonatal hearts, and finally in the clinical setting
during open-heart surgery through three Specific Aims. In Specific Aim 1, we will advance our approaches for
cardiac tissue discrimination in normal and congenitally deformed human hearts. We will characterize atrial,
ventricular, sinoatrial node, atrioventricular node and His bundle tissue using three-dimensional reconstructions
from conventional scanning confocal microscopy. The studies will be complemented with real-time FCM
imaging of these tissue. In Specific Aim 2, we will evaluate the ability of real-time FCM to guide pediatric heart
surgery using an ovine model of the cardioplegic arrested neonatal heart. The tissue imaging will be performed
by two different techniques of dye delivery; through the aortic root versus local surface application. Additionally,
the tissue, which is identified as tissue of the conduction system will be dissected out for analysis and
validation. In Specific Aim 3, we will study the microstructure of nodal tissues in-vivo in patients undergoing
cardiac surgery. We will initially study this in patients undergoing a simple cardiac surgical procedure.
Subsequently, we will randomize patients to FCM imaging versus standard surgical repair groups. We will
investigate the impact of intraoperative FCM use on the incidence of postoperative conduction abnormalities.
We hypothesize that using FCM will help decrease the incidence of postoperative conduction problems. All
specific aims are designed towards testing our hypothesis that real-time FCM allows surgeons to discriminate
between working myoc...

## Key facts

- **NIH application ID:** 9998776
- **Project number:** 5R01HL135077-04
- **Recipient organization:** BOSTON CHILDREN'S HOSPITAL
- **Principal Investigator:** Robert Hitchcock
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $492,949
- **Award type:** 5
- **Project period:** 2017-09-01 → 2022-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9998776

## Citation

> US National Institutes of Health, RePORTER application 9998776, Evaluation of Fiberoptic Confocal Microscopy for Pediatric Cardiac Surgery (5R01HL135077-04). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/9998776. Licensed CC0.

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