Cardiovascular magnetic resonance evaluation and risk stratification of myocardial diseases

Pauli Pöyhönen

Research output: ThesisDoctoral ThesisCollection of Articles

Abstract

Advanced cardiovascular magnetic resonance (CMR) may provide information of the myocardium beyond conventional imaging. The present thesis was designed to assess whether myocardial tissue characterization by CMR improves the diagnostic and prognostic evaluation of non-ischemic cardiomyopathies (NICMs) (studies I-III) and ischemic heart disease (IV). The specific objectives were (I) to evaluate the prognostic value of late gadolinium enhancement (LGE) and wall motion abnormality index (WMAi) compared to traditional risk factors in suspected NICM; (II) to assess the clinical and imaging predictors of severe cardiac inflammation, i.e. cardiac sarcoidosis (CS) or giant cell myocarditis (GCM); (III) to define the imaging characteristics of PRKAG2, a unique glycogen storage cardiomyopathy, which have not been systematically reported by CMR; (IV) to evaluate the nature of left ventricular (LV) remodeling by repeated CMR after revascularized myocardial infarction (MI), with specific attention to non-transmural infarcts. In studies (I-II), a retrospective cohort of 86 consecutive patients referred for CMR due to suspected NICM was identified. Patients with ischemic heart disease were excluded. CMR images were analysed for LGE and WMAi. Patients were followed-up for (I) major adverse cardiac events (MACEs) and (II) final diagnoses. In study (III), CMR and genetic testing were performed in two families harboring PRKAG2 mutations. In study (IV), altogether 41 patients underwent prospectively repeated CMR during the recovery phase (7 – 30 days), and the chronic infarct phase (≥ 6 months), after the first revascularized MI. Transmural MI was defined as ≥75% enhancement in at least one myocardial segment. We found that (I) in suspected NICM, LGE gives additional prognostic information compared to left ventricular ejection fraction (LVEF) and sustained ventricular tachycardia, while the absence of WMAi may give prognostic information beyond normal LVEF. The cumulative event ratio after three years was 4% in patients without LGE, 26% with LGE, and 43% with LGE ≥17% of LV muscle volume. Patients without WMAi did not experience MACEs. In study (II), LGE extent and sustained ventricular tachycardia predicted independently CS or GCM. Especially, multifocal LGE was useful in identifying severe cardiac inflammation, with 52-fold unadjusted odds ratio. In study (III), altogether six individuals had a PRKAG2 mutation: five with a known R302Q mutation (family 1), and one with a novel H344P mutation (family 2). We found that PRKAG2 cardiomyopathy may present with eccentric distribution of left ventricular hypertrophy, involving focal mid-infero-lateral pattern in the early disease stage, and more diffuse pattern but focusing on interventricular septum in advanced cases. We also found that in patients at earlier stages of disease, T1 values may be reduced, while in the advanced disease stage T1 mapping may result in higher values caused by fibrosis. In study (IV), we found that peak CK-MB has a strong association with chronic scar size and WMAi after revascularized non-transmural MI. Moreover, considerable infarct resorption happened after the first-month recovery phase, and LV mass resorption was related to age, being more common in younger patients. In conclusion, extensive amount of LGE should be considered as a sign of poor prognosis in NICM, even though the final diagnosis is uncertain. LGE, especially multifocally distributed, is useful in identification of severe cardiac inflammation. CMR is a valuable tool in detecting diffuse and focal myocardial abnormalities in PRKAG2 cardiomyopathy. Peak CK-MB provides robust estimation of infarct size and predicts chronic LV function after revascularized MI.
Original languageEnglish
Supervisors/Advisors
  • Rajala, Helena , Supervisor, External person
  • Holmström, Miia Maria, Supervisor
Place of PublicationHelsinki
Publisher
Print ISBNs978-951-51-4460-7
Electronic ISBNs978-951-51-4461-4
Publication statusPublished - 2018
MoE publication typeG5 Doctoral dissertation (article)

Fields of Science

  • Magnetic Resonance Imaging
  • AMP-Activated Protein Kinases
  • +genetics
  • Myocarditis
  • +diagnostic imaging
  • Sarcoidosis
  • Giant Cells
  • Ventricular Remodeling
  • Heart Ventricles
  • Cardiomyopathies
  • Myocardial Infarction
  • Inflammation
  • Heart
  • Fibrosis
  • Image Enhancement
  • Fractional Flow Reserve, Myocardial
  • Tachycardia, Ventricular
  • Risk
  • Gadolinium
  • Creatine Kinase, MB Form
  • Fluorodeoxyglucose F18
  • 3121 Internal medicine
  • 3126 Surgery, anesthesiology, intensive care, radiology

Cite this

Pöyhönen, Pauli. / Cardiovascular magnetic resonance evaluation and risk stratification of myocardial diseases. Helsinki : Helsingin yliopisto, 2018. 95 p.
@phdthesis{16eb12e112b54b49b41b1e34b9c9f889,
title = "Cardiovascular magnetic resonance evaluation and risk stratification of myocardial diseases",
abstract = "Advanced cardiovascular magnetic resonance (CMR) may provide information of the myocardium beyond conventional imaging. The present thesis was designed to assess whether myocardial tissue characterization by CMR improves the diagnostic and prognostic evaluation of non-ischemic cardiomyopathies (NICMs) (studies I-III) and ischemic heart disease (IV). The specific objectives were (I) to evaluate the prognostic value of late gadolinium enhancement (LGE) and wall motion abnormality index (WMAi) compared to traditional risk factors in suspected NICM; (II) to assess the clinical and imaging predictors of severe cardiac inflammation, i.e. cardiac sarcoidosis (CS) or giant cell myocarditis (GCM); (III) to define the imaging characteristics of PRKAG2, a unique glycogen storage cardiomyopathy, which have not been systematically reported by CMR; (IV) to evaluate the nature of left ventricular (LV) remodeling by repeated CMR after revascularized myocardial infarction (MI), with specific attention to non-transmural infarcts. In studies (I-II), a retrospective cohort of 86 consecutive patients referred for CMR due to suspected NICM was identified. Patients with ischemic heart disease were excluded. CMR images were analysed for LGE and WMAi. Patients were followed-up for (I) major adverse cardiac events (MACEs) and (II) final diagnoses. In study (III), CMR and genetic testing were performed in two families harboring PRKAG2 mutations. In study (IV), altogether 41 patients underwent prospectively repeated CMR during the recovery phase (7 – 30 days), and the chronic infarct phase (≥ 6 months), after the first revascularized MI. Transmural MI was defined as ≥75{\%} enhancement in at least one myocardial segment. We found that (I) in suspected NICM, LGE gives additional prognostic information compared to left ventricular ejection fraction (LVEF) and sustained ventricular tachycardia, while the absence of WMAi may give prognostic information beyond normal LVEF. The cumulative event ratio after three years was 4{\%} in patients without LGE, 26{\%} with LGE, and 43{\%} with LGE ≥17{\%} of LV muscle volume. Patients without WMAi did not experience MACEs. In study (II), LGE extent and sustained ventricular tachycardia predicted independently CS or GCM. Especially, multifocal LGE was useful in identifying severe cardiac inflammation, with 52-fold unadjusted odds ratio. In study (III), altogether six individuals had a PRKAG2 mutation: five with a known R302Q mutation (family 1), and one with a novel H344P mutation (family 2). We found that PRKAG2 cardiomyopathy may present with eccentric distribution of left ventricular hypertrophy, involving focal mid-infero-lateral pattern in the early disease stage, and more diffuse pattern but focusing on interventricular septum in advanced cases. We also found that in patients at earlier stages of disease, T1 values may be reduced, while in the advanced disease stage T1 mapping may result in higher values caused by fibrosis. In study (IV), we found that peak CK-MB has a strong association with chronic scar size and WMAi after revascularized non-transmural MI. Moreover, considerable infarct resorption happened after the first-month recovery phase, and LV mass resorption was related to age, being more common in younger patients. In conclusion, extensive amount of LGE should be considered as a sign of poor prognosis in NICM, even though the final diagnosis is uncertain. LGE, especially multifocally distributed, is useful in identification of severe cardiac inflammation. CMR is a valuable tool in detecting diffuse and focal myocardial abnormalities in PRKAG2 cardiomyopathy. Peak CK-MB provides robust estimation of infarct size and predicts chronic LV function after revascularized MI.",
keywords = "Magnetic Resonance Imaging, AMP-Activated Protein Kinases, +genetics, Myocarditis, +diagnostic imaging, Sarcoidosis, Giant Cells, Ventricular Remodeling, Heart Ventricles, Cardiomyopathies, Myocardial Infarction, Inflammation, Heart, Fibrosis, Image Enhancement, Fractional Flow Reserve, Myocardial, Tachycardia, Ventricular, Risk, Gadolinium, Creatine Kinase, MB Form, Fluorodeoxyglucose F18, 3121 Internal medicine, 3126 Surgery, anesthesiology, intensive care, radiology",
author = "Pauli P{\"o}yh{\"o}nen",
note = "M1 - 95 s. + liitteet",
year = "2018",
language = "English",
isbn = "978-951-51-4460-7",
series = "Dissertationes Scholae Doctoralis Ad Sanitatem Investigandam Universitatis Helsinkiensis",
publisher = "Helsingin yliopisto",
number = "55/2018",
address = "Finland",

}

Cardiovascular magnetic resonance evaluation and risk stratification of myocardial diseases. / Pöyhönen, Pauli.

Helsinki : Helsingin yliopisto, 2018. 95 p.

Research output: ThesisDoctoral ThesisCollection of Articles

TY - THES

T1 - Cardiovascular magnetic resonance evaluation and risk stratification of myocardial diseases

AU - Pöyhönen, Pauli

N1 - M1 - 95 s. + liitteet

PY - 2018

Y1 - 2018

N2 - Advanced cardiovascular magnetic resonance (CMR) may provide information of the myocardium beyond conventional imaging. The present thesis was designed to assess whether myocardial tissue characterization by CMR improves the diagnostic and prognostic evaluation of non-ischemic cardiomyopathies (NICMs) (studies I-III) and ischemic heart disease (IV). The specific objectives were (I) to evaluate the prognostic value of late gadolinium enhancement (LGE) and wall motion abnormality index (WMAi) compared to traditional risk factors in suspected NICM; (II) to assess the clinical and imaging predictors of severe cardiac inflammation, i.e. cardiac sarcoidosis (CS) or giant cell myocarditis (GCM); (III) to define the imaging characteristics of PRKAG2, a unique glycogen storage cardiomyopathy, which have not been systematically reported by CMR; (IV) to evaluate the nature of left ventricular (LV) remodeling by repeated CMR after revascularized myocardial infarction (MI), with specific attention to non-transmural infarcts. In studies (I-II), a retrospective cohort of 86 consecutive patients referred for CMR due to suspected NICM was identified. Patients with ischemic heart disease were excluded. CMR images were analysed for LGE and WMAi. Patients were followed-up for (I) major adverse cardiac events (MACEs) and (II) final diagnoses. In study (III), CMR and genetic testing were performed in two families harboring PRKAG2 mutations. In study (IV), altogether 41 patients underwent prospectively repeated CMR during the recovery phase (7 – 30 days), and the chronic infarct phase (≥ 6 months), after the first revascularized MI. Transmural MI was defined as ≥75% enhancement in at least one myocardial segment. We found that (I) in suspected NICM, LGE gives additional prognostic information compared to left ventricular ejection fraction (LVEF) and sustained ventricular tachycardia, while the absence of WMAi may give prognostic information beyond normal LVEF. The cumulative event ratio after three years was 4% in patients without LGE, 26% with LGE, and 43% with LGE ≥17% of LV muscle volume. Patients without WMAi did not experience MACEs. In study (II), LGE extent and sustained ventricular tachycardia predicted independently CS or GCM. Especially, multifocal LGE was useful in identifying severe cardiac inflammation, with 52-fold unadjusted odds ratio. In study (III), altogether six individuals had a PRKAG2 mutation: five with a known R302Q mutation (family 1), and one with a novel H344P mutation (family 2). We found that PRKAG2 cardiomyopathy may present with eccentric distribution of left ventricular hypertrophy, involving focal mid-infero-lateral pattern in the early disease stage, and more diffuse pattern but focusing on interventricular septum in advanced cases. We also found that in patients at earlier stages of disease, T1 values may be reduced, while in the advanced disease stage T1 mapping may result in higher values caused by fibrosis. In study (IV), we found that peak CK-MB has a strong association with chronic scar size and WMAi after revascularized non-transmural MI. Moreover, considerable infarct resorption happened after the first-month recovery phase, and LV mass resorption was related to age, being more common in younger patients. In conclusion, extensive amount of LGE should be considered as a sign of poor prognosis in NICM, even though the final diagnosis is uncertain. LGE, especially multifocally distributed, is useful in identification of severe cardiac inflammation. CMR is a valuable tool in detecting diffuse and focal myocardial abnormalities in PRKAG2 cardiomyopathy. Peak CK-MB provides robust estimation of infarct size and predicts chronic LV function after revascularized MI.

AB - Advanced cardiovascular magnetic resonance (CMR) may provide information of the myocardium beyond conventional imaging. The present thesis was designed to assess whether myocardial tissue characterization by CMR improves the diagnostic and prognostic evaluation of non-ischemic cardiomyopathies (NICMs) (studies I-III) and ischemic heart disease (IV). The specific objectives were (I) to evaluate the prognostic value of late gadolinium enhancement (LGE) and wall motion abnormality index (WMAi) compared to traditional risk factors in suspected NICM; (II) to assess the clinical and imaging predictors of severe cardiac inflammation, i.e. cardiac sarcoidosis (CS) or giant cell myocarditis (GCM); (III) to define the imaging characteristics of PRKAG2, a unique glycogen storage cardiomyopathy, which have not been systematically reported by CMR; (IV) to evaluate the nature of left ventricular (LV) remodeling by repeated CMR after revascularized myocardial infarction (MI), with specific attention to non-transmural infarcts. In studies (I-II), a retrospective cohort of 86 consecutive patients referred for CMR due to suspected NICM was identified. Patients with ischemic heart disease were excluded. CMR images were analysed for LGE and WMAi. Patients were followed-up for (I) major adverse cardiac events (MACEs) and (II) final diagnoses. In study (III), CMR and genetic testing were performed in two families harboring PRKAG2 mutations. In study (IV), altogether 41 patients underwent prospectively repeated CMR during the recovery phase (7 – 30 days), and the chronic infarct phase (≥ 6 months), after the first revascularized MI. Transmural MI was defined as ≥75% enhancement in at least one myocardial segment. We found that (I) in suspected NICM, LGE gives additional prognostic information compared to left ventricular ejection fraction (LVEF) and sustained ventricular tachycardia, while the absence of WMAi may give prognostic information beyond normal LVEF. The cumulative event ratio after three years was 4% in patients without LGE, 26% with LGE, and 43% with LGE ≥17% of LV muscle volume. Patients without WMAi did not experience MACEs. In study (II), LGE extent and sustained ventricular tachycardia predicted independently CS or GCM. Especially, multifocal LGE was useful in identifying severe cardiac inflammation, with 52-fold unadjusted odds ratio. In study (III), altogether six individuals had a PRKAG2 mutation: five with a known R302Q mutation (family 1), and one with a novel H344P mutation (family 2). We found that PRKAG2 cardiomyopathy may present with eccentric distribution of left ventricular hypertrophy, involving focal mid-infero-lateral pattern in the early disease stage, and more diffuse pattern but focusing on interventricular septum in advanced cases. We also found that in patients at earlier stages of disease, T1 values may be reduced, while in the advanced disease stage T1 mapping may result in higher values caused by fibrosis. In study (IV), we found that peak CK-MB has a strong association with chronic scar size and WMAi after revascularized non-transmural MI. Moreover, considerable infarct resorption happened after the first-month recovery phase, and LV mass resorption was related to age, being more common in younger patients. In conclusion, extensive amount of LGE should be considered as a sign of poor prognosis in NICM, even though the final diagnosis is uncertain. LGE, especially multifocally distributed, is useful in identification of severe cardiac inflammation. CMR is a valuable tool in detecting diffuse and focal myocardial abnormalities in PRKAG2 cardiomyopathy. Peak CK-MB provides robust estimation of infarct size and predicts chronic LV function after revascularized MI.

KW - Magnetic Resonance Imaging

KW - AMP-Activated Protein Kinases

KW - +genetics

KW - Myocarditis

KW - +diagnostic imaging

KW - Sarcoidosis

KW - Giant Cells

KW - Ventricular Remodeling

KW - Heart Ventricles

KW - Cardiomyopathies

KW - Myocardial Infarction

KW - Inflammation

KW - Heart

KW - Fibrosis

KW - Image Enhancement

KW - Fractional Flow Reserve, Myocardial

KW - Tachycardia, Ventricular

KW - Risk

KW - Gadolinium

KW - Creatine Kinase, MB Form

KW - Fluorodeoxyglucose F18

KW - 3121 Internal medicine

KW - 3126 Surgery, anesthesiology, intensive care, radiology

M3 - Doctoral Thesis

SN - 978-951-51-4460-7

T3 - Dissertationes Scholae Doctoralis Ad Sanitatem Investigandam Universitatis Helsinkiensis

PB - Helsingin yliopisto

CY - Helsinki

ER -

Pöyhönen P. Cardiovascular magnetic resonance evaluation and risk stratification of myocardial diseases. Helsinki: Helsingin yliopisto, 2018. 95 p. (Dissertationes Scholae Doctoralis Ad Sanitatem Investigandam Universitatis Helsinkiensis; 55/2018).