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  • Carlo Nicola De Cecco
  • Marco Rengo
Chapter
Part of the A-Z Notes in Radiological Practice and Reporting book series (AZRPR)

Keywords

Infective Endocarditis Tricuspid Valve Rheumatic Heart Disease Takayasu Arteritis Transcatheter Aortic Valve Replacement 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Takayasu Arteritis

  • Also known as “pulseless disease.”

  • Necrotizing and obliterative large-vessel panarteritis, which affects mostly young women (80 %).

  • Inflammatory process leads to occlusion and narrowing of the aorta and its branches.

  • Aortic involvement is common, wherein the abdominal aorta is the most affected, followed by the descending thoracic aorta and aortic arch.

  • Aneurysmal evolution and rupture of the affected aortic segments are not uncommon.

  • CT/MR: in early-stage crescentic or ringlike aortic thickening of more than 3 mm.

  • Numano Group Classification:
    • Type I: sovra-aortic vessels.

    • Type IIa: ascending aorta and/or aortic arch; sovra-aortic vessels may be affected.

    • Type IIb: descending aorta with/without ascending aorta and/or sovra-aortic vessel involvement.

    • Type III: descending aorta, thoracic aorta, and/or renal artery involvement; no involvement of ascending aorta, aortic arch, and sovra-aortic vessels.

    • Type IV: abdominal aorta and/or renal arteries.

    • Type V: whole aorta involvement.

    • Note: coronary and pulmonary artery involvement is reported as C + and P + .

  • Differential diagnosis: (1) large-vessel acute infections (mycotic aneurysm); (2) chronic infections (syphilis and TBC, especially in HIV patients); (3) radiation-induced fibromuscular dysplasia; (4) juvenile atherosclerosis.

Takotsubo Cardiomyopathy

  • Acute onset of chest pain and completely reversible regional contractile dysfunction, usually in the LV apical region.

  • Probably due to transient coronary vasospasm secondary to stressful condition.

  • MR: (1) apical LV akinesia; (2) apical myocardial edema; (3) no LE.

  • Differential diagnosis: acute myocardial infarct.

Tamponade, Cardiac

  • Low or rapid accumulation of blood, fluid, gas, or neoplastic tissue in pericardial cavity.

  • Classification: (1) acute; (2) subacute; (3) occult (low pressure).

  • Characteristics: (1) diastolic collapse of RV free wall and RA (first sign of RA collapse but unspecific); (2) dilated IVC with no inspiratory collapse.

Taussig–Bing Syndrome

  • Congenital disease in which the aorta arises from the right ventricle and the pulmonary artery arises from both ventricles associated with VSD.

Test Bolus

  • To calculate CEMRA acquisition time: (contrast arrival time + 1/2 injection time) - center K space.

Tetralogy of Fallot

  • Commonest cyanotic congenital cardiac disease.

  • Characteristics: (1) large nonrestrictive VSD; (2) overriding aorta; (3) RVOT obstruction; (4) RV hypertrophy.

  • The commonest cyanotic cardiac disease presenting outside the neonatal period.

  • Overriding aorta: 50 % of the aorta is beyond the interventricular septal crest.

  • Surgical repair: (1) VSD closure with Gore-Tex® or pericardium patch; (2) RVOT obstruction relief by transannular patching, valvectomy, or placing a homograft/conduit between the right ventricle and pulmonary artery.

  • Surgical correction in infant with transannular or infundibular patch, depending on the anatomy.

  • Dilatation of the RV in repaired tetralogy of Fallot is common and due to significant pulmonary regurgitation. Pulmonary valve implantation, either surgical or transcatheter, is needed in severe RV dilatation (iRVEDV > 150 ml/m2) to avoid RV failure and malignant arrhythmias.

  • Always look at branch pulmonary artery stenosis or dilatation quantifying the split pulmonary artery forward flow.

  • Post-contrast 3D SSFP navigator sequence in sagittal acquisition to better understand intracardiac and thoracic congenital and postsurgical anatomy.

  • Relationship between coronaries (particularly LCA) and RVOT is very important for percutaneous pulmonary valve implantation.

Thalassemia

  • See Iron Overload.

Tissue Doppler Imaging

  • TDI: echocardiography technique to assess the displacement of low velocity structure.

  • Accurate way to assess regional ventricle wall motion or track mitral/tricuspid annular motion and correlate it with ventricular systolic function or relaxation.

Total Cavopulmonary Connection

  • Palliative operation for patient with univentricular heart.

  • IVC connected to pulmonary artery using an intra-atrial tunnel combined with a Glenn shunt to SVC.

  • See also Fontan Intervention.

Transcatheter Aortic Valve Replacement

  • TAVR: alternative treatment in high-risk patients with severe aortic stenosis and other comorbidities.

  • A retrograde transarterial technique (femoral or subclavian artery) or an antegrade transapical implantation technique via the tip of the left ventricle is utilized.

  • Optimal positioning of the transcatheter aortic prosthesis relative to the annulus is critical.

  • Valve positioned too high: (1) increased risk of paravalvular regurgitation; (2) aortic injury; (3) embolization into the aorta.

  • Valve positioned too low: (1) mitral valve dysfunction; (2) heart block; (3) paravalvular regurgitation; (4) embolization into the left ventricle.

  • CT: (1) anatomic assessment of the aortic root structures; (2) course of the descending aorta and the iliofemoral access.

  • Accurate analysis and measurement of the annulus are crucial for correct selection of prosthesis size and type and to avoid damage of the annulus.

  • Complete evaluation of coronary anatomy with regard to the relationship between leaflet height and distance between annulus and coronary ostia, which identifies patients at risk for coronary occlusion during the procedure (a distance <10 mm).

  • Aortic valve evaluation: tricuspid or bicuspid, location and quantitative assessment of valve calcification, valve planimetry.

  • Measurement of the aortic sinus diameter, sinotubular junction, ascending and descending aorta (significant aneurysmal dilatation is a contraindication; the presence of extensive atherosclerotic plaque is likely associated with complications including stroke).

  • Iliofemoral arteries evaluation: size of the iliofemoral arteries, vessel calcifications and tortuosity (to avoid vascular complications such as access site hemorrhage/hematoma or central embolization).

Transesophageal Echocardiography

  • TOE indications: (1) valve disease; (2) cardiac source of embolism (PFO); (3) aortic disease; (4) endocarditis; (5) cardiac masses; (6) congenital heart disease; (7) prior cardioversion; (8) intraoperative monitoring of valve procedures; (9) interventional procedures.

  • Blind spot: Distal part of the ascending aorta and proximal aortic arch for the interposition of the trachea and right bronchus. Aortic dissection can be missed.

Transplantation, Cardiac

  • Two types: (1) orthotopic, the patient’s heart is removed and replaced with the donor heart; (2) heterotopic, the patient’s heart is left in place to support the donor heart.

  • Two techniques: (1) biatrial; (2) bicaval.

  • Mean postoperative survival: 15 years.

  • CT: (1) coronary arteries, to assess coronary allograft vasculopathy (concentric narrowing of the lumen for intimal hyperplasia); (2) heart chambers; (3) cardiac function; (4) opportunistic lung infections and malignancies secondary to immunosuppression.

  • Beta-blockers are ineffective in transplanted patient to reduce cardiac frequency because the heart is denervated.

  • MR: (1) graft-versus-host disease detection, diffuse myocardial LE; (2) myocardial ischemia and infarct secondary to coronary allograft vasculopathy; (3) heart chambers; (4) cardiac function.

Transposition of the Great Arteries

  • Congenital anomaly in which the aorta arises from the right ventricle and the pulmonary artery from the left ventricle.

  • The commonest cyanotic cardiac disease presenting in newborns.

  • Palliative Rashkind procedure for newborns: transcatheter atrial septostomy.

  • Surgical correction: arterial switch (LeCompte/French maneuver) or atrial switch (Mustard or Senning procedure).

  • After arterial switch look for branch pulmonary artery stenosis (vessel caliber, poststenotic dilatation, and flow acceleration/reduction).

  • After atrial switch SVC and IVC baffles redirect systemic venous return to the subpulmonary left heart; baffles might be obstructed or leaky.

  • MR: (1) cardiac function (in atrial switch the systemic RV function might be compromised with tricuspid regurgitation, especially after years from the correction); (2) do SVC and IVC flows and look at the azygos caliber and flow direction; (3) perform 3D SSFP navigator sequence to visualize origin and proximal course of reimplanted coronaries (exclude gross kinking/coronary obstruction); (4) LE assessment.

Tricuspid Atresia

  • No direct communication between the right atrium and the right ventricle.

  • Two types: (1) absence of right atrioventricular connection with an areolar sulcus tissue (fatty tissue) occupying the gap; (2) presence of an atretic valve (less common).

Tricuspid Valve

  • Three leaflets: septal, inferior, and anterosuperior (occasionally are two or four leaflets).

  • Apically displaced and usually thinner than the mitral valve.

  • The valve orifice is larger than the mitral orifice. Normal tricuspid valve between 3 and 5 cm2.

Tricuspid Valve Regurgitation

  • Trivial regurgitation is a common finding in normal subjects.

  • Causes: (1) right ventricular failure; (2) rheumatic heart disease; (3) infective endocarditis; (4) congenital; (5) carcinoid; (6) rheumatoid arthritis; (7) trauma; (8) prolapse.

  • Predictor bad outcome in ToF for arrhythmias.

  • CT: (1) Evaluate leaflet morphology and thickening; (2) assess for incomplete leaflet coaptation in the end-systolic phase; (3) evaluate the presence of reflux of contrast material into the IVC and hepatic veins during the first pass of contrast material.

  • MR: (1) The jet is usually visualized in LA view; sometimes the jet is difficult to visualize because of turbulence; use PC in LA view. (2) A set of transaxial images on the right ventricle provides additional informations, particularly for abnormal leaflet morphology such as in Ebstein’s anomaly. (3) SA cine view in systole, positioned through the tricuspid valve tips, permits to visualize the regurgitant orifice; through-plane PC at the same plane may give clearer delineation of flow through the orifice and permits to measure the diameter of the regurgitant orifice area; the regurgitant orifice is often noncircular.

  • Quantitative flow measurements:
    • Quantification can be achieved using pulmonary flow measurement, combined with RV stroke volume to calculate the regurgitant volume (RV stroke volume – pulmonary forward flow) and the regurgitant fraction (TR/RV stroke volume × 100 %).

    • Quantification can be also achieved using the difference in ventricular stroke volumes if only a single valve leak is present.

Table 1

Tricuspid valve regurgitation severity

Tricuspid valve regurgitation

Degree

Regurgitation fraction (%)

Orifice diameter (ml)

Mild

≤30

<2

Moderate

31–50

2–7

Severe

>50

>7

Tricuspid Valve Stenosis

  • Isolated form is uncommon.

  • Causes: (1) rheumatic heart disease (almost always); (2) congenital tricuspid atresia; (3) right atrial tumors; (4) carcinoid syndrome; (5) obstruction to right ventricular inflow (endomyocardial fibrosis, tricuspid valve vegetations, pacemaker lead, extracardiac tumors, Ebstein’s anomaly); (6) fusion and shortening of the chordae tendineae and the leaflets at their edges, determining a diaphragm with a fixed central aperture.

  • CT/MR: (1) Valve planimetry; (2) evaluate leaflet morphology and thickening; (3) assess for cusp non-apposition in the end-systolic phase.

  • Quantitative flow measurements:
    • Evaluate early and late peak velocities.

    • Calculate mean transvalvular gradient.

Table 2

Tricuspid valve stenosis severity

Tricuspid valve stenosis

Degree

Valve area (cm2)

Mild

>7

Moderate

1–7

Severe

<7

Troponin

  • Cardiac troponin: I and T.

  • Marker of myocardial damage.

  • Definition of myocardial necrosis for MI: maximal concentration of cTn exceeding the 99th percentile of values (>0.01 ng/mL) for a reference control group on at least one occasion during the first 24 h after the clinical event.

  • Diagnostic cutoff: high-sensitivity cTn >0.04 ng/mL.

  • In case of diagnostic incertitude for MI: look at cTn kinetic (serial troponin testing: 1 h after pain onset, 6–9 h and 12–24 h).

  • Other causes of elevated plasma cardiac troponin other than acute coronary syndrome: (1) cardiac (myocarditis/pericarditis, aortic dissection, acute/chronic heart failure, HCM, post-PCI, cardiac surgery, cardiac contusion, aortic valve disease); (2) noncardiac (pulmonary embolism, pulmonary hypertension, renal failure, stroke, amyloidosis, sepsis, extensive burn, cardiotoxic drug).

Truncus Arteriosus

  • Congenital disease in which aorta and pulmonary artery arise from a common trunk with a single truncal valve associated with a large VSD.

  • Associated lesions: (1) interrupted aortic arch; (2) aortic coarctation, (3) ASD.

  • Surgery in the 1 month of life to create separate outflow tracts.

  • Correction with interposition of RV to Pulmonary arteries conduit.

  • Complications: stenosis of the outflow tracts or valvular regurgitation.

Tumors, Cardiac

  • Incidence: 0.1–0.3 %.

  • Benign tumors more common than malignant.

  • Metastases are the commonest cardiac malignancy.

  • MR: (1) lesion detection and infiltration; (2) mass motion; (3) T1 and T2 signal; (4) STIR hyperintensity, suggestive of malignancy; (5) perfusional study, rapid contrast washout suggestive of malignancy; (6) early enhancement, thrombi detection; (7) LE study, area of necrosis and contrast sequestration; (8) pleural effusion, suggestive of malignancy.

  • CT: (1) lesion detection and infiltration; (2) mass motion; (3) thrombus detection; (4) tumor contrast enhancement; (5) lung metastasis or primitive lesion.

Turner’s Syndrome

  • Genetic disorder resulting from the absence of one X chromosome.

  • Major characteristics: (1) aortic coarctation; (2) absence of secondary sexual characteristics; (3) short stature; (4) lymphedema.

Suggested Reading

  1. Bogot NR et al (2007) Cardiac CT of the transplanted heart: indications, technique, appearance, and complications. Radiographics 27:1297–1309CrossRefPubMedGoogle Scholar
  2. Halefoglu AM et al (2005) Role of magnetic resonance imaging in the early diagnosis of Takayasu arteritis. Australas Radiol 49:377–381CrossRefPubMedGoogle Scholar
  3. Kilner PJ (2011) Imaging congenital heart disease in adults. Br J Radiol 84:S258–S268PubMedCentralCrossRefPubMedGoogle Scholar
  4. Mahajan VS et al (2011) How to interpret elevated cardiac troponin levels. Circulation 124:2350–2354CrossRefPubMedGoogle Scholar
  5. Nakamori S et al (2012) Prevalence and signal characteristics of late gadolinium enhancement on contrast-enhanced magnetic resonance imaging in patients with takotsubo cardiomyopathy. Circ J 76:914–921CrossRefPubMedGoogle Scholar
  6. Schmidt WA (2013) Imaging in vasculitis. Best Pract Res Clin Rheumatol 27:107–118CrossRefPubMedGoogle Scholar
  7. Taylor JT et al (2013) Contemporary management of tricuspid regurgitation: an updated clinical review. Cardiol Rev 21(4):174–183CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag Italia 2014

Authors and Affiliations

  • Carlo Nicola De Cecco
    • 1
    • 2
  • Marco Rengo
    • 1
  1. 1.Department of Radiological Sciences, Oncology and PathologySapienza University of Rome-Polo PontinoLatinaItaly
  2. 2.Department of Radiology and Radiological SciencesMedical University of South CarolinaCharlestonUSA

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