Atrial function — CMR phenotype documentation

Left Atrium

The vastly dynamic left atrium (LA) and its response to the stretch and secretion of atrial neuro-peptides leaves the LA far from being a simple transport chamber (Mehrzad, Rajab, and Spodick 2014). Left atrial function has been typically divided into three integrated phases: reservoir, conduit and booster-pump (Mehrzad, Rajab, and Spodick 2014; Alfuhied et al. 2021; Sun and Park 2021). During ventricular systole and isovolumetric relaxation, the LA acts as a ‘reservoir,’ receiving blood flow from the pulmonary veins due to a decrease in filling pressure, leading to an increase in LA size (expansion phase) (Mehrzad, Rajab, and Spodick 2014; Alfuhied et al. 2021; Sun and Park 2021). The conduit phase begins with LV diastole and continues up to the active LA contraction. It reflects passive emptying of the LA into the LV, governed by the transient LA to LV pressure gradient. During the early- and mid-conduit phase, the atrium functions as a conduit for transport of blood (about 75%) from the pulmonary veins to the LV. This transport continues until it is interrupted by active atrial contraction (Mehrzad, Rajab, and Spodick 2014; Alfuhied et al. 2021; Sun and Park 2021; Smiseth et al. 2024). During LA contraction, the LA myocardial wall actively contracts and pumps the remaining blood (about 25%). Finally, the LA cycle returns to the starting point with minimal LA volume (Sun and Park 2021).

The LA reservoir especially represents atrial relaxation and compliance influenced by the descent of the LV base during systole. LA conduit relies on atrial compliance during ventricular diastole, and it is closely related to LV relaxation and stiffness. Finally, LA booster reflects the intrinsic atrial contractility, which is modulated by the degree of venous return and LV diastolic compliance and pressure (Cau et al. 2022).

Emptying Fraction

After volumetric assessment of the LA at its maximum, minimum, and immediately before atrial systole, the total, passive, and active LA emptying fractions (LA EFs) can be calculated, reflecting reservoir, conduit, and booster pump functions, respectively (Hoit 2014; Wandelt et al. 2017).

Definition and calculation: The percentage reduction in left atrial volume from its maximal value to its minimal value during the cardiac cycle.
- Total EF: $\frac{LAV_{max}-LAV_{min}}{LAV_{max}}$ reflects the LA global and reservoir function (Hoit 2014; Wandelt et al. 2017; Doria De Vasconcellos et al. 2021; Alfuhied et al. 2021).
- Passive EF: $\frac{LAV_{max}-LAV_{pre-A}}{LAV_{max}}$ reflects LA conduit function (Hoit 2014; Wandelt et al. 2017; Doria De Vasconcellos et al. 2021; Alfuhied et al. 2021).
- Active EF: $\frac{LAV_{pre-A}-LAV_{min}}{LAV_{pre-A}}$ reflects LA booster pump function (Hoit 2014; Wandelt et al. 2017; Doria De Vasconcellos et al. 2021; Alfuhied et al. 2021).
Acquisition Type: LAX

Reference Range:

Total EF:

Study	Cohort Size	Gender	Age	Reference Value (%)	Note
(Kawel-Boehm et al. 2020)	534	male		(62, 8)	biplane area-length method, LAA excluded
	578	female		(63, 8)	biplane area-length method, LAA excluded
	66	male		(54, 8)	Simpson’s method, LAA excluded
	69	female		(57, 6)	Simpson’s method, LAA excluded
	196	male		(59, 8)	Simpson’s method, LAA included
	238	female		(61, 7)	Simpson’s method, LAA included
(Shang et al. 2018)	35			(58.8, 7.9)	16 males, 19 females, average age 52.2 years
(Evin et al. 2016)	28		20-29	(57.4, 5.6)	14 males, 14 females
	36		30-49	(56.0, 7.5)	18 males, 18 females
	30		≥50	(56.5, 6.0)	15 males, 15 females
(Truong et al. 2019)	45	male		(57.8, 3.7)	average age 43 years
	67	female		(59.5, 3.5)	average age 41 years
(Doria De Vasconcellos et al. 2021)	2526			(56.1, 11)	1165 males, 1361 females, average age 68.4 years
(Hudsmith et al. 2005)	63	male		(55, 13)
	45	female		(53, 9)
(Williams et al. 2015)	50			(65.0, 11)	28 males, 22 females, average age 42.6 years
(Petersen et al. 2017)	368	male		47-73	measured in VLA
	432	female		49-74	measured in VLA
(Erdei et al. 2022)	12			(59, 5)	7 males, 5 females, average age 33 years
(Sharifov et al. 2023)	8			(58, 9)	6 males, 2 females
(Maceira et al. 2016)	10	male	20-29	50-71
	10	male	30-39	49-70
	10	male	40-49	48-69
	10	male	50-59	47-68
	10	male	60-69	46-67
	10	male	70-79	45-66
	10	female	20-29	52-76
	10	female	30-39	50-74
	10	female	40-49	49-73
	10	female	50-59	47-71
	10	female	60-69	46-70
	10	female	70-79	44-68

Passive EF:

Study	Cohort Size	Gender	Age	Reference Value (%)	Note
(Shang et al. 2018)	35			(39.4, 11.2)	16 males, 19 females, average age 52.2 years
(Truong et al. 2019)	45	male		(38.4, 6.4)	average age 43 years
	67	female		(39.8, 6.1)	average age 41 years
(Doria De Vasconcellos et al. 2021)	2526			(23.8, 8)	1165 males, 1361 females, average age 68.4 years
(Williams et al. 2015)	50			(41.6, 13)	28 males, 22 females, average age 42.6 years
(Erdei et al. 2022)	12			(42, 10)	7 males, 5 females, average age 33 years
(Sharifov et al. 2023)	8			(34, 13)	6 males, 2 females
(Maceira et al. 2016)	10	male	20-29	31-53
	10	male	30-39	28-50
	10	male	40-49	24-46
	10	male	50-59	21-43
	10	male	60-69	18-40
	10	male	70-79	14-36
	10	female	20-29	34-59
	10	female	30-39	31-56
	10	female	40-49	27-52
	10	female	50-59	23-49
	10	female	60-69	20-45
	10	female	70-79	16-41

Active EF:

Study	Cohort Size	Gender	Age	Reference Value (%)	Note
(Shang et al. 2018)	35			(30.5, 14.3)	16 males, 19 females, average age 52.2 years
(Truong et al. 2019)	45	male		(31.1, 6.5)	average age 43 years
	67	female		(32.3, 5.9)	average age 41 years
(Doria De Vasconcellos et al. 2021)	2526			(42.6,11.4)	1165 males, 1361 females, average age 68.4 years
(Williams et al. 2015)	50			(39.9, 114)	28 males, 22 females, average age 42.6 years
(Erdei et al. 2022)	12			(29, 7)	7 males, 5 females, average age 33 years
(Sharifov et al. 2023)	8			(35, 14)	6 males, 2 females
(Maceira et al. 2016)	10	male	20-29	21-44
	10	male	30-39	23-45
	10	male	40-49	24-47
	10	male	50-59	26-48
	10	male	60-69	28-50
	10	male	70-79	29-52

Clinical Associations: LA EF is more powerful than LV EF or indexed LA volume in predicting heart failure outcomes and all-cause mortality (Hoit 2014). All three fractions are associated with CAD severity (Sharifov et al. 2023) and are affected in patients with HCM (Williams et al. 2015; Grassedonio et al. 2015). Total and passive LA EF are impaired in patients with T2DM (Shang et al. 2018) and in those with persistent or non-valvular AF (Habibi et al. 2014; Hoit 2014). Total and active LAEF are also significant independent predictors of all-cause mortality (Hoit 2014). In addition, total LAEF is reduced in patients with HFpEF (Kanagala et al. 2020) and hypertension (Gupta et al. 2013). A cutoff of 36% can distinguish grade II–III DD from grade I (Aquaro et al. 2019).
ICC:
- Total EF: 0.54
- Passive EF: Note: 0.42
- Active EF: Note: 0.35

Expansion Index

Definition and calculation: The ratio of the increase in left atrial volume from its minimal value to its maximal value during the cardiac cycle $\frac{LAV_{max}-LAV_{min}}{LAV_{min}}$ (Hoit 2014; Hsu et al. 2020).
Acquisition Type: LAX

Reference Range:

Study	Cohort Size	Gender	Age	Reference Value (%)	Note
(Shang et al. 2018)	35			(151.5, 46.8)	16 males, 19 females, average age 52.2 years
(Williams et al. 2015)	50			(219.0, 113)	28 males, 22 females, average age 42.6 years
(Maceira et al. 2016)	10	male	20-29	94-218
	10	male	30-39	88-212
	10	male	40-49	83-207
	10	male	50-59	77-201
	10	male	60-69	71-195
	10	male	70-79	65-189
	10	female	20-29	100-268
	10	female	30-39	89-257
	10	female	40-49	78-246
	10	female	50-59	67-235
	10	female	60-69	56-224
	10	female	70-79	45-213
(Hsu et al. 2020)	73	male	21-30	(179, 107)
	97	male	31-40	(162, 79)
	169	male	41-50	(162, 99)
	243	male	51-60	(146, 87)
	176	male	61-70	(129, 63)
	177	male	71-80	(126, 74)
	77	female	21-30	(188, 98)
	131	female	31-40	(160, 78)
	217	female	41-50	(166, 92)
	240	female	51-60	(149, 84)
	199	female	61-70	(125, 65)
	116	female	71-80	(122, 72)

Clinical Associations: Similar to LA EF, LA expansion index is reduced in patients with T2DM (Shang et al. 2018). It has been shown to outperform total LAEF in assessing DD (Hsu et al. 2020).
ICC: 0.50

Peak Emptying Rate (PER)

Peak emptying rate (PER) can be derived in a similar manner as peak filling rate (PFR).

<figure> <img src="/latex/images/atrium/PER.png" id="fig:PER" alt="Volume/time (V/t) curve and dV/dt curve of left atrium from which early peak emptying rate and atrial peak emptying rate can be derived (Aquaro et al. 2019)." /><figcaption aria-hidden="true">Volume/time (V/t) curve and dV/dt curve of left atrium from which early peak emptying rate and atrial peak emptying rate can be derived <span>(Aquaro et al. 2019)</span>.</figcaption> </figure>

Definition: Early peak emptying rate (PER-E) is the first negative peak of the atrial dV/dt curve. Late atrial peak emptying rate (PER-A) is the second negative peak during the booster phase (Aquaro et al. 2019).
Acquisition Type: LAX

Reference Range:

PER-E:

Study	Cohort Size	Gender	Age	Reference Value (mL/s)	Note
(Aquaro et al. 2019)	25			(152, 55)	11 males, 9 females, average age 51 years
(Erdei et al. 2022)	12			(313, 83)	7 males, 5 females, average age 33 years
(Sharifov et al. 2023)	8			(137, 44)	6 males, 2 females
(Maceira et al. 2016)	10	male	20-29	211-457
	10	male	30-39	173-419
	10	male	40-49	134-380
	10	male	50-59	96-342
	10	male	60-69	57-303
	10	male	70-79	19-265
	10	female	20-29	71-296
	10	female	30-39	88-314
	10	female	40-49	106-331
	10	female	50-59	124-349
	10	female	60-69	141-366
	10	female	70-79	159-384
(Grassedonio et al. 2015)	43			(227,86)	19 males, 24 females, average age 41 years

PER-A:

Study	Cohort Size	Gender	Age	Reference Value (mL/s)	Note
(Aquaro et al. 2019)	25			(159, 47)	11 males, 9 females, average age 51 years
(Erdei et al. 2022)	12			(171, 83)	7 males, 5 females, average age 33 years
(Sharifov et al. 2023)	8			(95, 44)	6 males, 2 females
(Maceira et al. 2016)	10	male	20-29	187-477
	10	male	30-39	144-435
	10	male	40-49	101-392
	10	male	50-59	59-349
	10	male	60-69	16-307
	10	male	70-79	324-647
	10	female	20-29	37-240
	10	female	30-39	52-255
	10	female	40-49	68-271
	10	female	50-59	83-286
	10	female	60-69	99-302
	10	female	70-79	114-317
(Grassedonio et al. 2015)	43			(216,104)	19 males, 24 females, average age 41 years

Note: Derived PER-A is higher than the reference range

Clinical Associations: Significant differences in PER-E and PER-A have been observed in patients with HCM (Grassedonio et al. 2015). Both rates can be indexed by LV filling volume for improved comparability. Patients with HOCM show a lower PER-E index (Bi et al. 2022), and the PER-A index can distinguish grade I DD from healthy controls and other patient groups (Aquaro et al. 2017).
ICC:
- PER-E: Note: 0.48
- PER-A: 0.55

Strain*

Whereas myocardial strain imaging has traditionally been applied to study the LV, it is currently implemented also as a tool for the quantification of LA function. The zero baseline can be defined using ventricular end-diastole. One advantage of such baseline is that this definition applies to all patients, including those in atrial fibrillation (Smiseth et al. 2024). Due to the peculiar fiber’s orientations and thinness of the atrial wall, only longitudinal strain is usually measured at the atrial level (Cau et al. 2022)l.

<figure> <img src="/latex/images/atrium/LA_strain_reference.png" id="fig:LA_strain_reference" alt="Strain nomenclature based on the choice of zero reference point. The left panel illustrates the case when the P-wave is defined as the zero reference, whereas the right panel illustrates the case when the QRS complex is defined as the zero reference (Hoit 2014)." /><figcaption aria-hidden="true">Strain nomenclature based on the choice of zero reference point. The left panel illustrates the case when the P-wave is defined as the zero reference, whereas the right panel illustrates the case when the QRS complex is defined as the zero reference <span>(Hoit 2014)</span>.</figcaption> </figure>

<figure> <img src="/latex/images/atrium/LA_strain.png" id="fig:LA_strain" alt="An illustration of the global LA strain. Arrows indicate reservoir strain, recoil strain and pump strain (Smiseth et al. 2024)." /><figcaption aria-hidden="true">An illustration of the global LA strain. Arrows indicate reservoir strain, recoil strain and pump strain <span>(Smiseth et al. 2024)</span>.</figcaption> </figure>

Definition and calculation: If the ventricular end-diastole (QRS complex) is defined as the zero reference, then the LA longitudinal strain can be decomposed into following components, each reflecting a distinct functional phase of atrial mechanics:
- Reservoir strain ε<sub>s</sub>: The peak positive longitudinal strain, calculated as the difference between peak strain and strain at ventricular end-diastole (Hoit 2014; Smiseth et al. 2024).
- Recoil strain ε<sub>e</sub>: The early diastolic strain, calculated as the difference between LA reservoir strain and pump strain, since the passive LA contraction after mitral valve opening is not a measure of conduit function (Hoit 2014; Smiseth et al. 2024).
- Booster pump strain ε<sub>a</sub>: The late diastolic strain, calculated as the difference between strain values at ventricular end-diastole and the onset of atrial contraction. Technically, it has a negative sign, but is most often reported as an absolute value (Hoit 2014; Smiseth et al. 2024).
Acquisition Type: LAX, Tagged MRI

Reference Range:

Reservoir strain:

Study	Cohort Size	Gender	Age	Reference Value (%)	Note
(Evin et al. 2016)	28		20-29	(25.6, 5.7)	14 males, 14 females
	36		30-49	(25.0, 5.4)	18 males, 18 females
	30		≥50	(21.2, 5.8)	15 males, 15 females
(Truong et al. 2019)	45	male		(37.6, 10.2)	average age 43 years
	67	female		(40.17, 8.5)	average age 41 years
(Habibi et al. 2014)	224			(38, 16)	149 males, 75 females, average age 67.7 years
(Habibi et al. 2015)	14			(33, 9)	10 males, 4 females, average age 43 years

Recoil strain:

Study	Cohort Size	Gender	Age	Reference Value (%)	Note
(Evin et al. 2016)	28		20-29	(13.3, 3.0)	14 males, 14 females
	36		30-49	(12.5, 3.3)	18 males, 18 females
	30		≥50	(9.0, 3.8)	15 males, 15 females
(Truong et al. 2019)	45	male		(23.79, 9.4)	average age 43 years
	67	female		(26.06, 7.46)	average age 41 years

Pump strain:

Study	Cohort Size	Gender	Age	Reference Value (%)	Note
(Evin et al. 2016)	28		20-29	(12.3, 3.9)	14 males, 14 females
	36		30-49	(12.5, 4.0)	18 males, 18 females
	30		≥50	(12.1, 4.0)	15 males, 15 females
(Truong et al. 2019)	45	male		(13.78, 4.05)	average age 43 years
	67	female		(14.12, 4.18)	average age 41 years

Clinical Associations: LA strain may be a more sensitive marker than EF and can predict post-operative AF, AF recurrence after ablation, outcomes in hypertrophic cardiomyopathy, stratification of diastolic dysfunction. LA strain also correlates with atrial fibrosis (Peters et al. 2021). Reservoir (peak) strain has diagnostic value for HF (Habibi et al. 2014), the severity of DD (Kim et al. 2020), severe CAD (Sharifov et al. 2023), and serves as a marker for future embolic events in AF as well as sudden cardiac death in HFpEF or acute MI (Park 2019). It is also an independent predictor of re-infarction, CHF hospitalization as well as all-cause mortality within 47 hours of an acute MI (Hoit 2014). Both LA reservoir and conduit strain are impaired in patients with hypertension, HCM, myocarditis, MR, AF, HFpEF, or Fontan circulation, while booster strain is also impaired in the presence of MR and AF (Cau et al. 2022). All three LA SRs are reduced in patients with persistent AF (Habibi et al. 2015).

Strain Rate*

<figure> <img src="/latex/images/atrium/LA_phase3.png" id="fig:LA_phase3" alt="Functions of the left atrium and their color-coded relation to the cardiac cycle. Displayed are pulmonary venous (PV) velocity, LA strain (\varepsilon), LA strain rate (SR), LA volume, left atrial pressure (LAP), and mitral spectral and tissue Doppler. Reservoir, conduit and booster pump functions are denoted by red, blue, and yellow lines, respectively (Hoit 2014)." /><figcaption aria-hidden="true">Functions of the left atrium and their color-coded relation to the cardiac cycle. Displayed are pulmonary venous (PV) velocity, LA strain (<span class="math inline"><em>ε</em></span>), LA strain rate (SR), LA volume, left atrial pressure (LAP), and mitral spectral and tissue Doppler. Reservoir, conduit and booster pump functions are denoted by red, blue, and yellow lines, respectively <span>(Hoit 2014)</span>.</figcaption> </figure>

Definition: The derivative of LA longitudinal strain, and can be similarly decomposed into distinct components corresponding to reservoir, conduit and booster-pump phases of atrial mechanics.
Acquisition Type: LAX

Reference Range:

Reservoir strain rate (SR-S):

Study	Cohort Size	Gender	Age	Reference Value (%/s)	Note
(Evin et al. 2016)	28		20-29	(1.3, 0.4)	14 males, 14 females
	36		30-49	(1.2, 0.4)	18 males, 18 females
	30		≥50	(0.9, 0.2)	15 males, 15 females
(Truong et al. 2019)	45	male		(1.94, 0.63)	average age 43 years
	67	female		(1.93, 0.48)	average age 41 years

Recoil strain rate (SR-E):

Study	Cohort Size	Gender	Age	Reference Value (%/s)	Note
(Evin et al. 2016)	28		20-29	(-1.4, 0.4)	14 males, 14 females
	36		30-49	(-1.2, 0.4)	18 males, 18 females
	30		≥50	(-0.8, 0.3)	15 males, 15 females
(Truong et al. 2019)	45	male		(-1.98, 0.69)	average age 43 years
	67	female		(-2.23, 0.68)	average age 41 years

Pump strain rate (SR-A):

Study	Cohort Size	Gender	Age	Reference Value (%/s)	Note
(Evin et al. 2016)	28		20-29	(-1.0, 0.4)	14 males, 14 females
	36		30-49	(-1.0, 0.4)	18 males, 18 females
	30		≥50	(-1.0, 0.4)	15 males, 15 females
(Truong et al. 2019)	45	male		(-2.04, 0.56)	average age 43 years
	67	female		(-2.03, 0.65)	average age 41 years

Clinical Associations: Decreases in reservoir and booster SRs are observed in HOCM (Williams et al. 2015), and conduit SR is also useful in diagnosing myocarditis and MR (Cau et al. 2022). Strain rate during the reservoir and conduit phases are significantly less in perm ant AF patients (Habibi et al. 2015).

Right Atrium

Although the right atrium (RA) is the least studied chamber, the RA, similar to the left atrium, comprises three functional exhibits three functional phases (Cau et al. 2022). However, few data exist on the clinical utility of right atrial strain (Smiseth et al. 2024).

Emptying Fraction

Acquisition Type: LAX

Reference Range:

Total EF:

Study	Cohort Size	Gender	Reference Value (%)	Note
(Kawel-Boehm et al. 2020)	66	male	(50, 9)	biplane area-length method, RAA excluded
	69	female	(56, 9)	biplane area-length method, RAA excluded
	66	male	(49, 10)	Simpson’s method, RAA excluded
	69	female	(54, 9)	Simpson’s method, RAA excluded
	256	male	(54, 10)	Simpson’s method, RAA included
	298	female	(59, 9)	Simpson’s method, RAA included
(Petersen et al. 2017)	363	male	23-58
	432	female	31-63

Strain and Strain Rate*

Acquisition Type: LAX
Reference Range:
One meta-analysis demonstrates a very wide reference range and significant inter-study heterogeneity for RA deformation among healthy subjects, which can be potentially explained by the use of different vendor and strain analysis software: The estimated normal range for RA reservoir strain is 25% to 63%, contractile strain 2% to 32%, conduit strain 7% to 28%. The estimated normal range for early diastolic strain rate is These may limit the utility of RA strain and strain rate in clinical practice. (Krittanawong et al. 2023).
Reported normal values can be found in (Krittanawong et al. 2023).
Clinical Associations: RA strains during both reservoir and conduit phases are independent predictors of heart failure, myocarditis, PAH and mortality (Jain et al. 2019; Cau et al. 2022; Lang et al. 2022). RA reservoir (peak) longitudinal strain has additive prognostic usefulness to other clinical measures in patients with PH, including RV strain and RA area (Hasselberg et al. 2021), and is an independent parameter associated with AF recurrence, more strongly associated with the recurrence of AF than LA reservoir longitudinal strain (Tomaselli et al. 2023).

Alfuhied, Aseel, Prathap Kanagala, Gerry P. McCann, and Anvesha Singh. 2021. “Multi-Modality Assessment and Role of Left Atrial Function as an Imaging Biomarker in Cardiovascular Disease.” The International Journal of Cardiovascular Imaging 37 (11): 3355–69.

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Aquaro, Giovanni Donato, Giovanni Camastra, Lorenzo Monti, Massimo Lombardi, Alessia Pepe, Silvia Castelletti, Viviana Maestrini, et al. 2017. “Reference Values of Cardiac Volumes, Dimensions, and New Functional Parameters by MR: A Multicenter, Multivendor Study.” Journal of Magnetic Resonance Imaging 45 (4): 1055–67.

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Aquaro, Giovanni Donato, Fausto Pizzino, Anna Terrizzi, Scipione Carerj, Bijoy K. Khandheria, and Gianluca Di Bella. 2019. “Diastolic Dysfunction Evaluated by Cardiac Magnetic Resonance: The Value of the Combined Assessment of Atrial and Ventricular Function.” European Radiology 29 (3): 1555–64.

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Bi, Xuanye, Yanyan Song, Chengzhi Yang, Yunhu Song, Shihua Zhao, Shubin Qiao, and Jinying Zhang. 2022. “Sex Differences in Atrial Remodeling and Its Relationship with Myocardial Fibrosis in Hypertrophic Obstructive Cardiomyopathy.” Frontiers in Cardiovascular Medicine 9: 947975.

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Cau, Riccardo, Pierpaolo Bassareo, Jasjit S. Suri, Gianluca Pontone, and Luca Saba. 2022. “The Emerging Role of Atrial Strain Assessed by Cardiac MRI in Different Cardiovascular Settings: An up-to-Date Review.” European Radiology 32 (7): 4384–94.

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Doria De Vasconcellos, Henrique, Theingi Tiffany Win, Ela Chamera, Seo Young Hong, Bharath Ambale Venkatesh, Patrick Young, Xiaoying Yang, et al. 2021. “References Values for Left Atrial Volumes, Emptying Fractions, Strains, and Strain Rates and Their Determinants by Age, Gender, and Ethnicity: The Multiethnic Study of Atherosclerosis (MESA).” Academic Radiology 28 (3): 356–63.

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Erdei, T., J. C. L. Rodrigues, R. Hartley-Davies, A. G. Dastidar, G. V. Szantho, E. C. Hart, A. K. Nightingale, N. E. Manghat, and M. C. K. Hamilton. 2022. “The Effect of Left Ventricular Longitudinal Strain on Left Atrial Function and Ventricular Filling in Hypertension.” Clinical Radiology 77 (5): e379–86.

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Evin, Morgane, Alban Redheuil, Gilles Soulat, Ludivine Perdrix, Golmehr Ashrafpoor, Alain Giron, Jérôme Lamy, et al. 2016. “Left Atrial Aging: A Cardiac Magnetic Resonance Feature-Tracking Study.” American Journal of Physiology-Heart and Circulatory Physiology 310 (5): H542–49.

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Grassedonio, Emanuele, Giancarlo Todiere, Ludovico La Grutta, Patrizia Toia, Giovanni D. Gentile, Massimo Galia, Federico Midiri, Alessia Pepe, Massimo Midiri, and Giovanni Donato Aquaro. 2015. “Assessment of Atrial Diastolic Function in Patients with Hypertrophic Cardiomyopathy by Cine Magnetic Resonance Imaging.” La Radiologia Medica 120 (8): 714–22.

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Gupta, Sachin, Susan A. Matulevicius, Colby R. Ayers, Jarett D. Berry, Parag C. Patel, David W. Markham, Benjamin D. Levine, et al. 2013. “Left Atrial Structure and Function and Clinical Outcomes in the General Population.” European Heart Journal 34 (4): 278–85.

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Habibi, Mohammadali, Harjit Chahal, Anders Opdahl, Ola Gjesdal, Thomas M. Helle-Valle, Susan R. Heckbert, Robyn McClelland, et al. 2014. “Association of CMR-Measured LA Function With Heart Failure Development.” JACC. Cardiovascular Imaging 7 (6): 570–79.

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