SVG image pattern position, different behaviour in IE

Question

I'm using this code with Snap.svg to create a pattern and then fill a path:

var s = Snap("#mysvg");
pattern = s.image(imgUrl, myX, myY, 200, 160).toPattern(myX, myY, 200, 160);
var frontHex = s.path(myPath).attr({
    fill: pattern
}); 

and the output is something like:

<svg id="mysvg">
<defs>
<pattern x="myX" y="myY" width="200" height="160" patternUnits="userSpaceOnUse" id="Si2mwvzou6" viewBox="myX myY 200 160">
    <image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="imgUrl" preserveAspectRatio="none" x="myX" y="myY" width="200" height="160"></image>
</pattern>
</defs>

<path d="myPath" fill="url('#Si2mwvzou6')"></path>
</svg>

The problem is that IE seems to work differently with pattern elements and in order to show the image in the right position I have to set the x and y of the image element always equals to 0.

pattern = s.image(imgUrl, 0, 0, 200, 160).toPattern(x, y, 200, 160);

output within the pattern element:

<image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="imgUrl" preserveAspectRatio="none meet" x="0" y="0" width="200" height="160"></image>

I thought to change the script when the client is using IE, but "Detect specific browsers" is not recommended and anyhow the user.agent trick doesn't work anymore: IE compatibility guidelines .

I never used Modernizr. Maybe this problem can be solved with it through feature detection? How?

Snap.svg automatically adds patternUnits="userSpaceOnUse" on pattern and preserveAspectRatio="none meet" on the image. There is something to do here maybe?

Update

I temporarily fixed the bug using this simple snippet:

var image = s.image(myUrl, x, y, 200, 160);
if(image.attr("preserveAspectRatio") === "none meet")
    image.attr({x: 0, y: 0});

It works for IE, Firefox and Chrome. I leave the question open, in case there are better or more correct solutions.