Characterization of subacute and convalescent fibrotic burden in the remote myocardium after acute infarction provides strong and incremental prediction of changes in left and right functions and final infarct size, incremental to knowledge of the subacute infarct size

The effect of the serotonin (5-hydroxytryptamine, 5-HT) antagonist ketanserin on the remote hemodynamic consequences of thrombotic brain infarction was studied in rats. Treated rats received an injection of 1 mg/kg ketanserin 30 min before and 1 h following photochemically induced cortical infarction. Local CBF (LCBF) was assessed autoradiographically with [14C]iodoantipyrine 4 h following infarction, and chronic infarct size was documented at 5 days. Thrombotic infarction led to significant decreases in LCBF within noninfarcted cortical regions. For example, mean LCBF was decreased to 63, 55, and 65% of control (nontreated normal rats) in ipsilateral frontal, lateral, and auditory cortices, respectively. In rats treated with ketanserin, significant decreases in LCBF were not documented within remote cortical areas compared with controls. In contrast to these hemodynamic effects, morphological analysis of chronic infarct size demonstrated no differences in infarct volume between treated (27 ± 3 mm3) and nontreated (27 ± 6 mm3) rats. These data are consistent with the hypothesis that 5-HT is involved in the widespread hemodynamic consequences of experimentally induced thrombotic infarction. Remote hemodynamic consequences of acute infarction can be inhibited without altering final infarct size.

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Early Diffusion-Weighted Imaging and Perfusion-Weighted Imaging Lesion Volumes Forecast Final Infarct Size in DEFUSE 2

Stroke ◽

10.1161/strokeaha.111.000135 ◽

2013 ◽

Vol 44 (3) ◽

pp. 681-685 ◽

Cited By ~ 72

Author(s):

Hayley M. Wheeler ◽

Michael Mlynash ◽

Manabu Inoue ◽

Aaryani Tipirneni ◽

John Liggins ◽

...

Keyword(s):

Infarct Size ◽

Diffusion Weighted Imaging ◽

Perfusion Weighted Imaging ◽

Diffusion Weighted ◽

Final Infarct Size

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Strain Echocardiography and Wall Motion Score Index Predicts Final Infarct Size in Patients With Non–ST-Segment–Elevation Myocardial Infarction

Circulation Cardiovascular Imaging ◽

10.1161/circimaging.109.910521 ◽

2010 ◽

Vol 3 (2) ◽

pp. 187-194 ◽

Cited By ~ 54

Author(s):

Christian Eek ◽

Bj�rnar Grenne ◽

Harald Brunvand ◽

Svend Aakhus ◽

Knut Endresen ◽

...

Keyword(s):

Myocardial Infarction ◽

Infarct Size ◽

Wall Motion ◽

Wall Motion Score Index ◽

St Segment Elevation ◽

Segment Elevation Myocardial Infarction ◽

St Segment ◽

Final Infarct Size ◽

Score Index ◽

Strain Echocardiography

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Abstract 13610: Native T1-based Cardiovascular Magnetic Resonance Imaging for Characterizing Chronic Myocardial Infarctions in Patients

Circulation ◽

10.1161/circ.130.suppl_2.13610 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Avinash Kali ◽

Eui Y Choi ◽

Behzad Sharif ◽

Young J Kim ◽

Xiaoming Bi ◽

...

Keyword(s):

Cardiovascular Magnetic Resonance ◽

Magnetic Resonance ◽

Infarct Size ◽

Sensitivity And Specificity ◽

Remote Myocardium ◽

Myocardial Infarctions ◽

Native T1 ◽

Threshold Criterion ◽

Acute Mi ◽

End Stage

Introduction: Late Gadolinium Enhancement (LGE) Cardiovascular Magnetic Resonance (CMR) is the gold standard for characterizing chronic myocardial infarctions (MIs), but it is contraindicated in patients with end-stage chronic kidney disease. Hypothesis: We investigated whether native T1 mapping at 3T can reliably characterize chronic MIs in two pilot patient populations with prior STEMI and NSTEMI. Methods: Patients with prior STEMI (n=15) and NSTEMI (n=17) underwent CMR at a median of 13.6 years after acute MI and native T1 maps and LGE images were acquired. Infarct location, size and transmurality were measured from LGE and T1 maps using standard threshold criterion and compared against one another. Visual conspicuity for detecting chronic MI territories on LGE images and T1 maps were assessed by independent reviewers. Results: LGE images and native T1 maps were not different for measuring infarct size (STEMI: p=0.87; NSTEMI: p=0.93) and transmurality (STEMI: p=0.19; NSTEMI: p=0.24). Statistical analyses showed good agreement between LGE images and T1 maps for measuring infarct size (STEMI: bias = -0.4±2.1%; R2=0.97; NSTEMI: bias = -1.1±3.9%; R2=0.87) and transmurality (STEMI: bias = 1.5±2.9%; R2=0.99; NSTEMI: bias = -2.2±7.4%; R2=0.71). Sensitivity and specificity of native T1 maps for detecting chronic MIs based on threshold criterion were 93% and 97% respectively (STEMI); and 93% and 92% respectively (NSTEMI). Mean visual conspicuity score for detecting chronic MI on LGE images was greater than that of native T1 maps (p<0.001). Sensitivity and specificity of native T1 maps using visual detection were: 61% and 85% (STEMI); and 67% and 90% (NSTEMI). Conclusions: Chronic MIs in STEMI and NSTEMI patients can be reliably characterized using threshold-based detection with native T1 maps when the location of remote myocardium is known. The current visual detectability of remote myocardium on native T1 maps has a certainty of 85% in STEMI and 90% in NSTEMI patients.

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Manganese-Enhanced T1 Mapping in the Myocardium of Normal and Infarcted Hearts

Contrast Media & Molecular Imaging ◽

10.1155/2018/9641527 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 5

Author(s):

N. B. Spath ◽

D. M. L. Lilburn ◽

G. A. Gray ◽

L. M. Le Page ◽

G. Papanastasiou ◽

...

Keyword(s):

Myocardial Infarction ◽

Contrast Media ◽

Infarct Size ◽

Calcium Channel ◽

Left Ventricular ◽

Remote Myocardium ◽

Inversion Recovery ◽

Left Ventricular Ejection ◽

Channel Blockade ◽

Calcium Channel Blockade

Background. Manganese-enhanced MRI (MEMRI) has the potential to identify viable myocardium and quantify calcium influx and handling. Two distinct manganese contrast media have been developed for clinical application, mangafodipir and EVP1001-1, employing different strategies to mitigate against adverse effects resulting from calcium-channel agonism. Mangafodipir delivers manganese ions as a chelate, and EVP1001-1 coadministers calcium gluconate. Using myocardial T1 mapping, we aimed to explore chelated and nonchelated manganese contrast agents, their mechanism of myocardial uptake, and their application to infarcted hearts. Methods. T1 mapping was performed in healthy adult male Sprague-Dawley rats using a 7T MRI scanner before and after nonchelated (EVP1001-1 or MnCl2 (22 μmol/kg)) or chelated (mangafodipir (22–44 μmol/kg)) manganese-based contrast media in the presence of calcium channel blockade (diltiazem (100–200 μmol/kg/min)) or sodium chloride (0.9%). A second cohort of rats underwent surgery to induce anterior myocardial infarction by permanent coronary artery ligation or sham surgery. Infarcted rats were imaged with standard gadolinium delayed enhancement MRI (DEMRI) with inversion recovery techniques (DEMRI inversion recovery) as well as DEMRI T1 mapping. A subsequent MEMRI scan was performed 48 h later using either nonchelated or chelated manganese and T1 mapping. Finally, animals were culled at 12 weeks, and infarct size was quantified histologically with Masson’s trichrome (MTC). Results. Both manganese agents induced concentration-dependent shortening of myocardial T1 values. This was greatest with nonchelated manganese, and could be inhibited by 30–43% with calcium-channel blockade. Manganese imaging successfully delineated the area of myocardial infarction. Indeed, irrespective of the manganese agent, there was good agreement between infarct size on MEMRI T1 mapping and histology (bias 1.4%, 95% CI −14.8 to 17.1 P>0.05). In contrast, DEMRI inversion recovery overestimated infarct size (bias 11.4%, 95% CI −9.1 to 31.8 P=0.002), as did DEMRI T1 mapping (bias 8.2%, 95% CI −10.7 to 27.2 P=0.008). Increased manganese uptake was also observed in the remote myocardium, with remote myocardial ∆T1 inversely correlating with left ventricular ejection fraction after myocardial infarction (r=−0.61, P=0.022). Conclusions. MEMRI causes concentration and calcium channel-dependent myocardial T1 shortening. MEMRI with T1 mapping provides an accurate assessment of infarct size and can also identify changes in calcium handling in the remote myocardium. This technique has potential applications for the assessment of myocardial viability, remodelling, and regeneration.

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On strong CNZ rings and their extensions

General Letters in Mathematics ◽

10.31559/glm2020.9.2.4 ◽

2020 ◽

Vol 9 (2) ◽

pp. 80-92

Author(s):

Chenar Abdul Kareem Ahmed

Keyword(s):

Nilpotent Elements ◽

Left And Right

T.K. Kwak and Y. Lee called a ring R satisfy the commutativity of nilpotent elements at zero[1] if ab = 0 for a, b ∈ N(R) implies ba = 0. For simplicity, a ring R is called CNZ if it satisfies the commutativity of nilpotent elements at zero. In this paper we study an extension of a CNZ ring with its endomorphism. An endomorphism α of a ring R is called strong right ( resp., left) CNZ if whenever aα(b) = 0(resp., α(a)b = 0 ) for a, b ∈ N(R) ba = 0. A ring R is called strong right (resp., left) α-CNZ if there exists a strong right (resp., left) CNZ endomorphism α of R, and the ring R is called strong α- CNZ if R is both strong left and right α- CNZ. Characterization of strong α- CNZ rings and their related properties including extensions are investigated . In particular, it’s shown that a ring R is reduced if and only if U2(R) is a CNZ ring. Furthermore extensions of strong α- CNZ rings are studied.

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Abstract 2667: Aspiration Coronary Thrombectomy for Acute Myocardial Infarction Improves Myocardial Salvage Index. Single Center Randomized Study

Circulation ◽

10.1161/circ.118.suppl_18.s_764-a ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Michal Ciszewski ◽

Jerzy Pregowski ◽

Anna Teresinska ◽

Maciej Karcz ◽

Witold Ruzyllo

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Infarct Size ◽

Perfusion Imaging ◽

Randomized Study ◽

Myocardial Salvage ◽

Aspiration Thrombectomy ◽

Acute Stemi ◽

Final Infarct Size ◽

Myocardium At Risk

Primary percutaneus intervention (pPCI) is a recommended treatment strategy for acute myocardial infarction with ST segment elevation (STEMI). Adjunctive thrombectomy may add clinical benefits. The aim of our study was to compare the efficacy of aspiration thrombectomy versus standard pPCI for STEMI. The primary endpoint was salvage index assessed by sestamibi SPECT perfusion imaging. Single centre randomized study on aspiration thrombectomy in acute STEMI. 135 patients (88 males, mean age 64,3±12,4 yrs) with first acute STEMI were enrolled between Nov 2004 and Dec 2007. Inclusion criteria were: first anterior or inferior STEMI within 12 hours from pain onset with culprit lesion in left anterior descending (LAD) or right coronary artery (RCA) and TIMI flow ≤ 2. Patients were randomly assigned to thrombectomy with Rescue or Diver device followed by stent implantation (65) vs. standard pPCI with stenting (70 pts). 5 patients initially randomised to thrombectomy were finally treated with standard pPCI. Two SPECT examinations were performed: before and 5– 8 days after reperfusion therapy. Five patients died 3–7 days after the procedure, and in 3 pts second SPECT could not be performed because of patients’ severe condition. Thus two SPECT examinations were performed in 127 patients (63 treated with thrombectomy and 64 in control group). These 127 subject were the basis of the intention to treat analyses. There were 41 pts with anterior STEMI and 86 pts with inferior STEMI. Both treatment groups were similar regarding baseline demographic and clinical variables. Based on the SPECT perfusion imaging results, the final infarct size was assessed and myocardial salvage index (proportion of the myocardium at risk salvaged by reperfusion) was calculated. Baseline myocardium at risk area was 35,0%±2,8% in thrombectomy group vs 35,8%±10,9% in control patients. (p=NS). Myocardial salvage index was larger in patients treated with aspiration thrombectomy (0,33±0,27 vs. 0,20 ± 0,21 p = 0,004). Moreover, final infarct size was significantly smaller in patients treated with thrombectomy: 23,9% ± 13,1 % vs.28,3 % ±9,6% p = 0,005. Our results show that coronary thrombectomy is beneficial as an adjunctive therapy to pPCI in STEMI.

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Characterization of the IS200/IS605 Insertion Sequence Family in Halanaerobium Hydrogeniformans

Genes ◽

10.3390/genes11050484 ◽

2020 ◽

Vol 11 (5) ◽

pp. 484

Author(s):

Michael Sadler ◽

Melanie R. Mormile ◽

Ronald L. Frank

Keyword(s):

Insertion Sequence ◽

Open Reading Frames ◽

Insertion Sequences ◽

Genome Plasticity ◽

Mobile Dna ◽

Dna Elements ◽

Left And Right ◽

Evolutionary Role ◽

Reading Frames

Mobile DNA elements play a significant evolutionary role by promoting genome plasticity. Insertion sequences are the smallest prokaryotic transposable elements. They are highly diverse elements, and the ability to accurately identify, annotate, and infer the full genomic impact of insertion sequences is lacking. Halanaerobium hydrogeniformans is a haloalkaliphilic bacterium with an abnormally high number of insertion sequences. One family, IS200/IS605, showed several interesting features distinct from other elements in this genome. Twenty-three loci harbor elements of this family in varying stages of decay, from nearly intact to an ends-only sequence. The loci were characterized with respect to two divergent open reading frames (ORF), tnpA and tnpB, and left and right ends of the elements. The tnpB ORF contains two nearly identical insert sequences that suggest recombination between tnpB ORF is occurring. From these results, insertion sequence activity can be inferred, including transposition capability and element interaction.

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